Bump version to 3.9.0

Without this, the websocket returns all messages on connection, which is very time consuming.

.github/workflows/pr-testing.yml

@@ -8,16 +8,16 @@ jobs:
   mavenTesting:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Cache local Maven repository
-      uses: actions/cache@v2
+      uses: actions/cache@v3
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
         restore-keys: |
           ${{ runner.os }}-maven-
     - name: Set up the Java JDK
-      uses: actions/setup-java@v2
+      uses: actions/setup-java@v3
       with:
         java-version: '11'
         distribution: 'adopt'

.gitignore

@@ -14,7 +14,6 @@
 /.mvn.classpath
 /notes*
 /settings.json
-/testnet*
 /settings*.json
 /testchain*.json
 /run-testnet*.sh

WindowsInstaller/Qortal.aip

@@ -17,10 +17,10 @@
     <ROW Property="Manufacturer" Value="Qortal"/>
     <ROW Property="MsiLogging" MultiBuildValue="DefaultBuild:vp"/>
     <ROW Property="NTP_GOOD" Value="false"/>
-    <ROW Property="ProductCode" Value="1033:{ADE0C9E9-F7D9-4829-8626-8571C735C4D7} 1049:{F5230C0A-9D8C-4C70-AC72-17CECC8273B8} 2052:{D5A0760C-E5B3-4C4C-97B0-81CC445F07B9} 2057:{EF5EF0BE-0B00-4F5C-A2A0-DF2CB82FF20D} " Type="16"/>
+    <ROW Property="ProductCode" Value="1033:{CB85115E-ECCE-4B3D-BB7F-6251A2764922} 1049:{09AC1C62-4E33-4312-826A-38F597ED1B17} 2052:{3CF701B3-E118-4A31-A4B7-156CEA19FBCC} 2057:{468F337D-0EF8-41D1-B5DE-4EEE66BA2AF6} " Type="16"/>
     <ROW Property="ProductLanguage" Value="2057"/>
     <ROW Property="ProductName" Value="Qortal"/>
-    <ROW Property="ProductVersion" Value="3.6.3" Type="32"/>
+    <ROW Property="ProductVersion" Value="3.8.5" Type="32"/>
     <ROW Property="RECONFIG_NTP" Value="true"/>
     <ROW Property="REMOVE_BLOCKCHAIN" Value="YES" Type="4"/>
     <ROW Property="REPAIR_BLOCKCHAIN" Value="YES" Type="4"/>
@@ -212,7 +212,7 @@
     <ROW Component="ADDITIONAL_LICENSE_INFO_71" ComponentId="{12A3ADBE-BB7A-496C-8869-410681E6232F}" Directory_="jdk.zipfs_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_71" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_8" ComponentId="{D53AD95E-CF96-4999-80FC-5812277A7456}" Directory_="java.naming_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_8" Type="0"/>
     <ROW Component="ADDITIONAL_LICENSE_INFO_9" ComponentId="{6B7EA9B0-5D17-47A8-B78C-FACE86D15E01}" Directory_="java.net.http_Dir" Attributes="0" KeyPath="ADDITIONAL_LICENSE_INFO_9" Type="0"/>
-    <ROW Component="AI_CustomARPName" ComponentId="{F4F774B9-18DC-4740-9552-EA16B98801C9}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
+    <ROW Component="AI_CustomARPName" ComponentId="{094B5D07-2258-4A39-9917-2E2F7F6E210B}" Directory_="APPDIR" Attributes="260" KeyPath="DisplayName" Options="1"/>
     <ROW Component="AI_ExePath" ComponentId="{3644948D-AE0B-41BB-9FAF-A79E70490A08}" Directory_="APPDIR" Attributes="260" KeyPath="AI_ExePath"/>
     <ROW Component="APPDIR" ComponentId="{680DFDDE-3FB4-47A5-8FF5-934F576C6F91}" Directory_="APPDIR" Attributes="0"/>
     <ROW Component="AccessBridgeCallbacks.h" ComponentId="{288055D1-1062-47A3-AA44-5601B4E38AED}" Directory_="bridge_Dir" Attributes="0" KeyPath="AccessBridgeCallbacks.h" Type="0"/>

pom.xml

@@ -3,7 +3,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>org.qortal</groupId>
 	<artifactId>qortal</artifactId>
-	<version>3.8.1</version>
+	<version>3.9.0</version>
 	<packaging>jar</packaging>
 	<properties>
 		<skipTests>true</skipTests>
@@ -304,6 +304,7 @@
 									implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
 									<mainClass>org.qortal.controller.Controller</mainClass>
 									<manifestEntries>
+										<Multi-Release>true</Multi-Release>
 										<Class-Path>. ..</Class-Path>
 									</manifestEntries>
 								</transformer>

src/main/java/org/qortal/api/model/ConnectedPeer.java

@@ -1,6 +1,7 @@
 package org.qortal.api.model;
 
 import io.swagger.v3.oas.annotations.media.Schema;
+import org.qortal.controller.Controller;
 import org.qortal.data.block.BlockSummaryData;
 import org.qortal.data.network.PeerData;
 import org.qortal.network.Handshake;
@@ -36,6 +37,7 @@ public class ConnectedPeer {
     public Long lastBlockTimestamp;
     public UUID connectionId;
     public String age;
+    public Boolean isTooDivergent;
 
     protected ConnectedPeer() {
     }
@@ -69,6 +71,11 @@ public class ConnectedPeer {
             this.lastBlockSignature = peerChainTipData.getSignature();
             this.lastBlockTimestamp = peerChainTipData.getTimestamp();
         }
+
+        // Only include isTooDivergent decision if we've had the opportunity to request block summaries this peer
+        if (peer.getLastTooDivergentTime() != null) {
+            this.isTooDivergent = Controller.wasRecentlyTooDivergent.test(peer);
+        }
     }
 
 }

src/main/java/org/qortal/api/resource/AdminResource.java

@@ -45,6 +45,7 @@ import org.qortal.block.BlockChain;
 import org.qortal.controller.Controller;
 import org.qortal.controller.Synchronizer;
 import org.qortal.controller.Synchronizer.SynchronizationResult;
+import org.qortal.controller.repository.BlockArchiveRebuilder;
 import org.qortal.data.account.MintingAccountData;
 import org.qortal.data.account.RewardShareData;
 import org.qortal.network.Network;
@@ -222,6 +223,42 @@ public class AdminResource {
 		}
 	}
 
+	@GET
+	@Path("/summary/alltime")
+	@Operation(
+			summary = "Summary of activity since genesis",
+			responses = {
+					@ApiResponse(
+							content = @Content(schema = @Schema(implementation = ActivitySummary.class))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public ActivitySummary allTimeSummary(@HeaderParam(Security.API_KEY_HEADER) String apiKey) {
+		Security.checkApiCallAllowed(request);
+
+		ActivitySummary summary = new ActivitySummary();
+
+		try (final Repository repository = RepositoryManager.getRepository()) {
+			int startHeight = 1;
+			long start = repository.getBlockRepository().fromHeight(startHeight).getTimestamp();
+			int endHeight = repository.getBlockRepository().getBlockchainHeight();
+
+			summary.setBlockCount(endHeight - startHeight);
+
+			summary.setTransactionCountByType(repository.getTransactionRepository().getTransactionSummary(startHeight + 1, endHeight));
+
+			summary.setAssetsIssued(repository.getAssetRepository().getRecentAssetIds(start).size());
+
+			summary.setNamesRegistered (repository.getNameRepository().getRecentNames(start).size());
+
+			return summary;
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@GET
 	@Path("/enginestats")
 	@Operation(
@@ -698,6 +735,64 @@ public class AdminResource {
 		}
 	}
 
+	@POST
+	@Path("/repository/archive/rebuild")
+	@Operation(
+			summary = "Rebuild archive",
+			description = "Rebuilds archive files, using the specified serialization version",
+			requestBody = @RequestBody(
+					required = true,
+					content = @Content(
+							mediaType = MediaType.TEXT_PLAIN,
+							schema = @Schema(
+									type = "number", example = "2"
+							)
+					)
+			),
+			responses = {
+					@ApiResponse(
+							description = "\"true\"",
+							content = @Content(mediaType = MediaType.TEXT_PLAIN, schema = @Schema(type = "string"))
+					)
+			}
+	)
+	@ApiErrors({ApiError.REPOSITORY_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String rebuildArchive(@HeaderParam(Security.API_KEY_HEADER) String apiKey, Integer serializationVersion) {
+		Security.checkApiCallAllowed(request);
+
+		// Default serialization version to value specified in settings
+		if (serializationVersion == null) {
+			serializationVersion = Settings.getInstance().getDefaultArchiveVersion();
+		}
+
+		try {
+			// We don't actually need to lock the blockchain here, but we'll do it anyway so that
+			// the node can focus on rebuilding rather than synchronizing / minting.
+			ReentrantLock blockchainLock = Controller.getInstance().getBlockchainLock();
+
+			blockchainLock.lockInterruptibly();
+
+			try {
+				BlockArchiveRebuilder blockArchiveRebuilder = new BlockArchiveRebuilder(serializationVersion);
+				blockArchiveRebuilder.start();
+
+				return "true";
+
+			} catch (IOException e) {
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA, e);
+
+			} finally {
+				blockchainLock.unlock();
+			}
+		} catch (InterruptedException e) {
+			// We couldn't lock blockchain to perform rebuild
+			return "false";
+		} catch (DataException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
+		}
+	}
+
 	@DELETE
 	@Path("/repository")
 	@Operation(

src/main/java/org/qortal/api/resource/ArbitraryResource.java

@@ -501,6 +501,9 @@ public class ArbitraryResource {
 			}
 
 			for (ArbitraryTransactionData transactionData : transactionDataList) {
+				if (transactionData.getService() == null) {
+					continue;
+				}
 				ArbitraryResourceInfo arbitraryResourceInfo = new ArbitraryResourceInfo();
 				arbitraryResourceInfo.name = transactionData.getName();
 				arbitraryResourceInfo.service = transactionData.getService();
@@ -719,7 +722,7 @@ public class ArbitraryResource {
 		try {
 			ArbitraryDataTransactionMetadata transactionMetadata = ArbitraryMetadataManager.getInstance().fetchMetadata(resource, false);
 			if (transactionMetadata != null) {
-				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
+				ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata, true);
 				if (resourceMetadata != null) {
 					return resourceMetadata;
 				}
@@ -773,6 +776,7 @@ public class ArbitraryResource {
 					   @QueryParam("description") String description,
 					   @QueryParam("tags") List<String> tags,
 					   @QueryParam("category") Category category,
+					   @QueryParam("fee") Long fee,
 					   String path) {
 		Security.checkApiCallAllowed(request);
 
@@ -781,7 +785,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, path, null, null, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 	@POST
@@ -818,6 +822,7 @@ public class ArbitraryResource {
 					   @QueryParam("description") String description,
 					   @QueryParam("tags") List<String> tags,
 					   @QueryParam("category") Category category,
+					   @QueryParam("fee") Long fee,
 					   String path) {
 		Security.checkApiCallAllowed(request);
 
@@ -826,7 +831,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, path, null, null, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 
@@ -864,6 +869,7 @@ public class ArbitraryResource {
 										@QueryParam("description") String description,
 										@QueryParam("tags") List<String> tags,
 										@QueryParam("category") Category category,
+										@QueryParam("fee") Long fee,
 										String base64) {
 		Security.checkApiCallAllowed(request);
 
@@ -872,7 +878,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, null, base64, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 	@POST
@@ -907,6 +913,7 @@ public class ArbitraryResource {
 										@QueryParam("description") String description,
 										@QueryParam("tags") List<String> tags,
 										@QueryParam("category") Category category,
+										@QueryParam("fee") Long fee,
 										String base64) {
 		Security.checkApiCallAllowed(request);
 
@@ -915,7 +922,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, null, base64, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 
@@ -952,6 +959,7 @@ public class ArbitraryResource {
 								 @QueryParam("description") String description,
 								 @QueryParam("tags") List<String> tags,
 								 @QueryParam("category") Category category,
+								 @QueryParam("fee") Long fee,
 								 String base64Zip) {
 		Security.checkApiCallAllowed(request);
 
@@ -960,7 +968,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, null, base64Zip, true,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 	@POST
@@ -995,6 +1003,7 @@ public class ArbitraryResource {
 								 @QueryParam("description") String description,
 								 @QueryParam("tags") List<String> tags,
 								 @QueryParam("category") Category category,
+								 @QueryParam("fee") Long fee,
 								 String base64Zip) {
 		Security.checkApiCallAllowed(request);
 
@@ -1003,7 +1012,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, null, base64Zip, true,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 
@@ -1043,6 +1052,7 @@ public class ArbitraryResource {
 							 @QueryParam("description") String description,
 							 @QueryParam("tags") List<String> tags,
 							 @QueryParam("category") Category category,
+							 @QueryParam("fee") Long fee,
 							 String string) {
 		Security.checkApiCallAllowed(request);
 
@@ -1051,7 +1061,7 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, null, null, string, null, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 	@POST
@@ -1088,6 +1098,7 @@ public class ArbitraryResource {
 							 @QueryParam("description") String description,
 							 @QueryParam("tags") List<String> tags,
 							 @QueryParam("category") Category category,
+							 @QueryParam("fee") Long fee,
 							 String string) {
 		Security.checkApiCallAllowed(request);
 
@@ -1096,14 +1107,14 @@ public class ArbitraryResource {
 		}
 
 		return this.upload(Service.valueOf(serviceString), name, identifier, null, string, null, false,
-				title, description, tags, category);
+				fee, title, description, tags, category);
 	}
 
 
 	// Shared methods
 
-	private String upload(Service service, String name, String identifier,
-						  String path, String string, String base64, boolean zipped,
+	private String upload(Service service, String name, String identifier, String path,
+						  String string, String base64, boolean zipped, Long fee,
 						  String title, String description, List<String> tags, Category category) {
 		// Fetch public key from registered name
 		try (final Repository repository = RepositoryManager.getRepository()) {
@@ -1128,7 +1139,7 @@ public class ArbitraryResource {
 			if (path == null) {
 				// See if we have a string instead
 				if (string != null) {
-					File tempFile = File.createTempFile("qortal-", ".tmp");
+					File tempFile = File.createTempFile("qortal-", "");
 					tempFile.deleteOnExit();
 					BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile.toPath().toString()));
 					writer.write(string);
@@ -1138,7 +1149,7 @@ public class ArbitraryResource {
 				}
 				// ... or base64 encoded raw data
 				else if (base64 != null) {
-					File tempFile = File.createTempFile("qortal-", ".tmp");
+					File tempFile = File.createTempFile("qortal-", "");
 					tempFile.deleteOnExit();
 					Files.write(tempFile.toPath(), Base64.decode(base64));
 					path = tempFile.toPath().toString();
@@ -1167,9 +1178,14 @@ public class ArbitraryResource {
 				}
 			}
 
+			// Default to zero fee if not specified
+			if (fee == null) {
+				fee = 0L;
+			}
+
 			try {
 				ArbitraryDataTransactionBuilder transactionBuilder = new ArbitraryDataTransactionBuilder(
-						repository, publicKey58, Paths.get(path), name, null, service, identifier,
+						repository, publicKey58, fee, Paths.get(path), name, null, service, identifier,
 						title, description, tags, category
 				);
 
@@ -1288,7 +1304,7 @@ public class ArbitraryResource {
 			ArbitraryDataResource resource = new ArbitraryDataResource(resourceInfo.name, ResourceIdType.NAME,
 					resourceInfo.service, resourceInfo.identifier);
 			ArbitraryDataTransactionMetadata transactionMetadata = resource.getLatestTransactionMetadata();
-			ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata);
+			ArbitraryResourceMetadata resourceMetadata = ArbitraryResourceMetadata.fromTransactionMetadata(transactionMetadata, false);
 			if (resourceMetadata != null) {
 				resourceInfo.metadata = resourceMetadata;
 			}

src/main/java/org/qortal/api/resource/BlocksResource.java

@@ -48,6 +48,7 @@ import org.qortal.repository.RepositoryManager;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.block.BlockTransformer;
 import org.qortal.utils.Base58;
+import org.qortal.utils.Triple;
 
 @Path("/blocks")
 @Tag(name = "Blocks")
@@ -165,10 +166,13 @@ public class BlocksResource {
             }
 
             // Not found, so try the block archive
-            byte[] bytes = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, false, repository);
-            if (bytes != null) {
-				if (version != 1) {
-					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Archived blocks require version 1");
+            Triple<byte[], Integer, Integer> serializedBlock = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, false, repository);
+            if (serializedBlock != null) {
+				byte[] bytes = serializedBlock.getA();
+				Integer serializationVersion = serializedBlock.getB();
+				if (version != serializationVersion) {
+					// TODO: we could quite easily reserialize the block with the requested version
+					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Block is not stored using requested serialization version.");
 				}
 				return Base58.encode(bytes);
             }
@@ -634,13 +638,16 @@ public class BlocksResource {
 	@ApiErrors({
 		ApiError.REPOSITORY_ISSUE
 	})
-	public List<BlockData> getBlockRange(@PathParam("height") int height, @Parameter(
-		ref = "count"
-	) @QueryParam("count") int count) {
+	public List<BlockData> getBlockRange(@PathParam("height") int height,
+										 @Parameter(ref = "count") @QueryParam("count") int count,
+										 @Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse,
+										 @QueryParam("includeOnlineSignatures") Boolean includeOnlineSignatures) {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			List<BlockData> blocks = new ArrayList<>();
+			boolean shouldReverse = (reverse != null && reverse == true);
 
-			for (/* count already set */; count > 0; --count, ++height) {
+			int i = 0;
+			while (i < count) {
 				BlockData blockData = repository.getBlockRepository().fromHeight(height);
 				if (blockData == null) {
 					// Not found - try the archive
@@ -650,8 +657,14 @@ public class BlocksResource {
 						break;
 					}
 				}
+				if (includeOnlineSignatures == null || includeOnlineSignatures == false) {
+					blockData.setOnlineAccountsSignatures(null);
+				}
 
 				blocks.add(blockData);
+
+				height = shouldReverse ? height - 1 : height + 1;
+				i++;
 			}
 
 			return blocks;

src/main/java/org/qortal/api/resource/BootstrapResource.java

@@ -60,7 +60,7 @@ public class BootstrapResource {
 			bootstrap.validateBlockchain();
 			return bootstrap.create();
 
-		} catch (DataException | InterruptedException | IOException e) {
+		} catch (Exception e) {
 			LOGGER.info("Unable to create bootstrap", e);
 			throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.REPOSITORY_ISSUE, e.getMessage());
 		}

src/main/java/org/qortal/api/resource/ChatResource.java

@@ -40,6 +40,8 @@ import org.qortal.utils.Base58;
 
 import com.google.common.primitives.Bytes;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @Path("/chat")
 @Tag(name = "Chat")
 public class ChatResource {
@@ -70,6 +72,10 @@ public class ChatResource {
 			@QueryParam("txGroupId") Integer txGroupId,
 			@QueryParam("involving") List<String> involvingAddresses,
 			@QueryParam("reference") String reference,
+			@QueryParam("chatreference") String chatReference,
+			@QueryParam("haschatreference") Boolean hasChatReference,
+			@QueryParam("sender") String sender,
+			@QueryParam("encoding") Encoding encoding,
 			@Parameter(ref = "limit") @QueryParam("limit") Integer limit,
 			@Parameter(ref = "offset") @QueryParam("offset") Integer offset,
 			@Parameter(ref = "reverse") @QueryParam("reverse") Boolean reverse) {
@@ -92,13 +98,21 @@ public class ChatResource {
 		if (reference != null)
 			referenceBytes = Base58.decode(reference);
 
+		byte[] chatReferenceBytes = null;
+		if (chatReference != null)
+			chatReferenceBytes = Base58.decode(chatReference);
+
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			return repository.getChatRepository().getMessagesMatchingCriteria(
 					before,
 					after,
 					txGroupId,
 					referenceBytes,
+					chatReferenceBytes,
+					hasChatReference,
 					involvingAddresses,
+					sender,
+					encoding,
 					limit, offset, reverse);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
@@ -121,7 +135,7 @@ public class ChatResource {
 			}
 	)
 	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
-	public ChatMessage getMessageBySignature(@PathParam("signature") String signature58) {
+	public ChatMessage getMessageBySignature(@PathParam("signature") String signature58, @QueryParam("encoding") Encoding encoding) {
 		byte[] signature = Base58.decode(signature58);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
@@ -131,7 +145,7 @@ public class ChatResource {
 				throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Message not found");
 			}
 
-			return repository.getChatRepository().toChatMessage(chatTransactionData);
+			return repository.getChatRepository().toChatMessage(chatTransactionData, encoding);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}
@@ -154,12 +168,12 @@ public class ChatResource {
 		}
 	)
 	@ApiErrors({ApiError.INVALID_CRITERIA, ApiError.INVALID_ADDRESS, ApiError.REPOSITORY_ISSUE})
-	public ActiveChats getActiveChats(@PathParam("address") String address) {
+	public ActiveChats getActiveChats(@PathParam("address") String address, @QueryParam("encoding") Encoding encoding) {
 		if (address == null || !Crypto.isValidAddress(address))
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_ADDRESS);
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			return repository.getChatRepository().getActiveChats(address);
+			return repository.getChatRepository().getActiveChats(address, encoding);
 		} catch (DataException e) {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.REPOSITORY_ISSUE, e);
 		}

src/main/java/org/qortal/api/resource/CrossChainBitcoinResource.java

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainBitcoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Bitcoin block height",
+		description = "Returns the height of the most recent block in the Bitcoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getBitcoinHeight() {
+		Bitcoin bitcoin = Bitcoin.getInstance();
+
+		try {
+			Integer height = bitcoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainBitcoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = bitcoin.getWalletBalanceFromTransactions(key58);
+			Long balance = bitcoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainBitcoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getUnusedBitcoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Bitcoin bitcoin = Bitcoin.getInstance();
+
+		if (!bitcoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return bitcoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainDigibyteResource.java

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainDigibyteResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Digibyte block height",
+		description = "Returns the height of the most recent block in the Digibyte chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getDigibyteHeight() {
+		Digibyte digibyte = Digibyte.getInstance();
+
+		try {
+			Integer height = digibyte.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainDigibyteResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = digibyte.getWalletBalanceFromTransactions(key58);
+			Long balance = digibyte.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainDigibyteResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getUnusedDigibyteReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Digibyte digibyte = Digibyte.getInstance();
+
+		if (!digibyte.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return digibyte.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainDogecoinResource.java

@@ -21,6 +21,7 @@ import org.qortal.crosschain.SimpleTransaction;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -33,6 +34,37 @@ public class CrossChainDogecoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Dogecoin block height",
+		description = "Returns the height of the most recent block in the Dogecoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getDogecoinHeight() {
+		Dogecoin dogecoin = Dogecoin.getInstance();
+
+		try {
+			Integer height = dogecoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -66,7 +98,7 @@ public class CrossChainDogecoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = dogecoin.getWalletBalanceFromTransactions(key58);
+			Long balance = dogecoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -116,6 +148,45 @@ public class CrossChainDogecoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getUnusedDogecoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Dogecoin dogecoin = Dogecoin.getInstance();
+
+		if (!dogecoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return dogecoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainHtlcResource.java

@@ -8,11 +8,10 @@ import io.swagger.v3.oas.annotations.responses.ApiResponse;
 import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
-import java.io.IOException;
 import java.math.BigDecimal;
 import java.util.List;
 import java.util.Objects;
-import java.util.concurrent.locks.ReentrantLock;
+import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.*;
@@ -25,7 +24,6 @@ import org.bitcoinj.core.*;
 import org.bitcoinj.script.Script;
 import org.qortal.api.*;
 import org.qortal.api.model.CrossChainBitcoinyHTLCStatus;
-import org.qortal.controller.Controller;
 import org.qortal.crosschain.*;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.at.ATData;
@@ -586,98 +584,103 @@ public class CrossChainHtlcResource {
 			}
 
 			List<TradeBotData> allTradeBotData = repository.getCrossChainRepository().getAllTradeBotData();
-			TradeBotData tradeBotData = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).findFirst().orElse(null);
-			if (tradeBotData == null)
+			List<TradeBotData> tradeBotDataList = allTradeBotData.stream().filter(tradeBotDataItem -> tradeBotDataItem.getAtAddress().equals(atAddress)).collect(Collectors.toList());
+			if (tradeBotDataList == null || tradeBotDataList.isEmpty())
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
-			Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
-			int lockTime = tradeBotData.getLockTimeA();
+			// Loop through all matching entries for this AT address, as there might be more than one
+			for (TradeBotData tradeBotData : tradeBotDataList) {
 
-			// We can't refund P2SH-A until lockTime-A has passed
-			if (NTP.getTime() <= lockTime * 1000L)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				if (tradeBotData == null)
+					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
-			// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
-			int medianBlockTime = bitcoiny.getMedianBlockTime();
-			if (medianBlockTime <= lockTime)
-				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				Bitcoiny bitcoiny = (Bitcoiny) acct.getBlockchain();
+				int lockTime = tradeBotData.getLockTimeA();
 
-			// Fee for redeem/refund is subtracted from P2SH-A balance.
-			long feeTimestamp = calcFeeTimestamp(lockTime, crossChainTradeData.tradeTimeout);
-			long p2shFee = bitcoiny.getP2shFee(feeTimestamp);
-			long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
+				// We can't refund P2SH-A until lockTime-A has passed
+				if (NTP.getTime() <= lockTime * 1000L)
+					continue;
 
-			// Create redeem script based on destination chain
-			byte[] redeemScriptA;
-			String p2shAddressA;
-			BitcoinyHTLC.Status htlcStatusA;
-			if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
-				redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-				p2shAddressA = PirateChain.getInstance().deriveP2shAddressBPrefix(redeemScriptA);
-				htlcStatusA = PirateChainHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-			}
-			else {
-				redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
-				p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
-				htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-			}
-			LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
+				// We can't refund P2SH-A until median block time has passed lockTime-A (see BIP113)
+				int medianBlockTime = bitcoiny.getMedianBlockTime();
+				if (medianBlockTime <= lockTime)
+					continue;
 
-			switch (htlcStatusA) {
-				case UNFUNDED:
-				case FUNDING_IN_PROGRESS:
-					// Still waiting for P2SH-A to be funded...
-					throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_TOO_SOON);
+				// Fee for redeem/refund is subtracted from P2SH-A balance.
+				long feeTimestamp = calcFeeTimestamp(lockTime, crossChainTradeData.tradeTimeout);
+				long p2shFee = bitcoiny.getP2shFee(feeTimestamp);
+				long minimumAmountA = crossChainTradeData.expectedForeignAmount + p2shFee;
 
-				case REDEEM_IN_PROGRESS:
-				case REDEEMED:
-				case REFUND_IN_PROGRESS:
-				case REFUNDED:
-					// Too late!
-					return false;
+				// Create redeem script based on destination chain
+				byte[] redeemScriptA;
+				String p2shAddressA;
+				BitcoinyHTLC.Status htlcStatusA;
+				if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+					redeemScriptA = PirateChainHTLC.buildScript(tradeBotData.getTradeForeignPublicKey(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+					p2shAddressA = PirateChain.getInstance().deriveP2shAddressBPrefix(redeemScriptA);
+					htlcStatusA = PirateChainHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+				} else {
+					redeemScriptA = BitcoinyHTLC.buildScript(tradeBotData.getTradeForeignPublicKeyHash(), lockTime, crossChainTradeData.creatorForeignPKH, tradeBotData.getHashOfSecret());
+					p2shAddressA = bitcoiny.deriveP2shAddress(redeemScriptA);
+					htlcStatusA = BitcoinyHTLC.determineHtlcStatus(bitcoiny.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+				}
+				LOGGER.info(String.format("Refunding P2SH address: %s", p2shAddressA));
 
-				case FUNDED:{
-					Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
+				switch (htlcStatusA) {
+					case UNFUNDED:
+					case FUNDING_IN_PROGRESS:
+						// Still waiting for P2SH-A to be funded...
+						continue;
 
-					if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
-						// Pirate Chain custom integration
+					case REDEEM_IN_PROGRESS:
+					case REDEEMED:
+					case REFUND_IN_PROGRESS:
+					case REFUNDED:
+						// Too late!
+						continue;
 
-						PirateChain pirateChain = PirateChain.getInstance();
-						String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA);
+					case FUNDED: {
+						Coin refundAmount = Coin.valueOf(crossChainTradeData.expectedForeignAmount);
 
-						// Get funding txid
-						String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddressA, minimumAmountA);
-						if (fundingTxidHex == null) {
-							throw new ForeignBlockchainException("Missing funding txid when refunding P2SH");
+						if (Objects.equals(bitcoiny.getCurrencyCode(), "ARRR")) {
+							// Pirate Chain custom integration
+
+							PirateChain pirateChain = PirateChain.getInstance();
+							String p2shAddressT3 = pirateChain.deriveP2shAddress(redeemScriptA);
+
+							// Get funding txid
+							String fundingTxidHex = PirateChainHTLC.getUnspentFundingTxid(pirateChain.getBlockchainProvider(), p2shAddressA, minimumAmountA);
+							if (fundingTxidHex == null) {
+								throw new ForeignBlockchainException("Missing funding txid when refunding P2SH");
+							}
+							String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
+
+							byte[] privateKey = tradeBotData.getTradePrivateKey();
+							String privateKey58 = Base58.encode(privateKey);
+							String redeemScript58 = Base58.encode(redeemScriptA);
+
+							String txid = PirateChain.getInstance().refundP2sh(p2shAddressT3,
+									receiveAddress, refundAmount.value, redeemScript58, fundingTxid58, lockTime, privateKey58);
+							LOGGER.info("Refund txid: {}", txid);
+						} else {
+							// ElectrumX coins
+
+							ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
+							List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
+
+							// Validate the destination foreign blockchain address
+							Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
+							if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
+								throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
+
+							Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
+									fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
+
+							bitcoiny.broadcastTransaction(p2shRefundTransaction);
 						}
-						String fundingTxid58 = Base58.encode(HashCode.fromString(fundingTxidHex).asBytes());
 
-						byte[] privateKey = tradeBotData.getTradePrivateKey();
-						String privateKey58 = Base58.encode(privateKey);
-						String redeemScript58 = Base58.encode(redeemScriptA);
-
-						String txid = PirateChain.getInstance().refundP2sh(p2shAddressT3,
-								receiveAddress, refundAmount.value, redeemScript58, fundingTxid58, lockTime, privateKey58);
-						LOGGER.info("Refund txid: {}", txid);
+						return true;
 					}
-					else {
-						// ElectrumX coins
-
-						ECKey refundKey = ECKey.fromPrivate(tradeBotData.getTradePrivateKey());
-						List<TransactionOutput> fundingOutputs = bitcoiny.getUnspentOutputs(p2shAddressA);
-
-						// Validate the destination foreign blockchain address
-						Address receiving = Address.fromString(bitcoiny.getNetworkParameters(), receiveAddress);
-						if (receiving.getOutputScriptType() != Script.ScriptType.P2PKH)
-							throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
-
-						Transaction p2shRefundTransaction = BitcoinyHTLC.buildRefundTransaction(bitcoiny.getNetworkParameters(), refundAmount, refundKey,
-								fundingOutputs, redeemScriptA, lockTime, receiving.getHash());
-
-						bitcoiny.broadcastTransaction(p2shRefundTransaction);
-					}
-
-					return true;
 				}
 			}
 

src/main/java/org/qortal/api/resource/CrossChainLitecoinResource.java

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainLitecoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Litecoin block height",
+		description = "Returns the height of the most recent block in the Litecoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getLitecoinHeight() {
+		Litecoin litecoin = Litecoin.getInstance();
+
+		try {
+			Integer height = litecoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainLitecoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = litecoin.getWalletBalanceFromTransactions(key58);
+			Long balance = litecoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainLitecoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getUnusedLitecoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Litecoin litecoin = Litecoin.getInstance();
+
+		if (!litecoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return litecoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainPirateChainResource.java

@@ -20,6 +20,7 @@ import org.qortal.crosschain.SimpleTransaction;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -32,6 +33,37 @@ public class CrossChainPirateChainResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current PirateChain block height",
+		description = "Returns the height of the most recent block in the PirateChain chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getPirateChainHeight() {
+		PirateChain pirateChain = PirateChain.getInstance();
+
+		try {
+			Integer height = pirateChain.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainRavencoinResource.java

@@ -14,6 +14,7 @@ import java.util.List;
 import javax.servlet.http.HttpServletRequest;
 import javax.ws.rs.HeaderParam;
 import javax.ws.rs.POST;
+import javax.ws.rs.GET;
 import javax.ws.rs.Path;
 import javax.ws.rs.core.Context;
 import javax.ws.rs.core.MediaType;
@@ -35,6 +36,37 @@ public class CrossChainRavencoinResource {
 	@Context
 	HttpServletRequest request;
 
+	@GET
+	@Path("/height")
+	@Operation(
+		summary = "Returns current Ravencoin block height",
+		description = "Returns the height of the most recent block in the Ravencoin chain.",
+		responses = {
+			@ApiResponse(
+				content = @Content(
+					schema = @Schema(
+						type = "number"
+					)
+				)
+			)
+		}
+	)
+	@ApiErrors({ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	public String getRavencoinHeight() {
+		Ravencoin ravencoin = Ravencoin.getInstance();
+
+		try {
+			Integer height = ravencoin.getBlockchainHeight();
+			if (height == null)
+				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+
+			return height.toString();
+
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/walletbalance")
 	@Operation(
@@ -68,7 +100,7 @@ public class CrossChainRavencoinResource {
 			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
 
 		try {
-			Long balance = ravencoin.getWalletBalanceFromTransactions(key58);
+			Long balance = ravencoin.getWalletBalance(key58);
 			if (balance == null)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
 
@@ -118,6 +150,45 @@ public class CrossChainRavencoinResource {
 		}
 	}
 
+	@POST
+	@Path("/unusedaddress")
+	@Operation(
+		summary = "Returns first unused address for hierarchical, deterministic BIP32 wallet",
+		description = "Supply BIP32 'm' private/public key in base58, starting with 'xprv'/'xpub' for mainnet, 'tprv'/'tpub' for testnet",
+		requestBody = @RequestBody(
+			required = true,
+			content = @Content(
+				mediaType = MediaType.TEXT_PLAIN,
+				schema = @Schema(
+					type = "string",
+					description = "BIP32 'm' private/public key in base58",
+					example = "tpubD6NzVbkrYhZ4XTPc4btCZ6SMgn8CxmWkj6VBVZ1tfcJfMq4UwAjZbG8U74gGSypL9XBYk2R2BLbDBe8pcEyBKM1edsGQEPKXNbEskZozeZc"
+				)
+			)
+		),
+		responses = {
+			@ApiResponse(
+				content = @Content(array = @ArraySchema( schema = @Schema( implementation = SimpleTransaction.class ) ) )
+			)
+		}
+	)
+	@ApiErrors({ApiError.INVALID_PRIVATE_KEY, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE})
+	@SecurityRequirement(name = "apiKey")
+	public String getUnusedRavencoinReceiveAddress(@HeaderParam(Security.API_KEY_HEADER) String apiKey, String key58) {
+		Security.checkApiCallAllowed(request);
+
+		Ravencoin ravencoin = Ravencoin.getInstance();
+
+		if (!ravencoin.isValidDeterministicKey(key58))
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_PRIVATE_KEY);
+
+		try {
+			return ravencoin.getUnusedReceiveAddress(key58);
+		} catch (ForeignBlockchainException e) {
+			throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.FOREIGN_BLOCKCHAIN_NETWORK_ISSUE);
+		}
+	}
+
 	@POST
 	@Path("/send")
 	@Operation(

src/main/java/org/qortal/api/resource/CrossChainTradeBotResource.java

@@ -11,6 +11,7 @@ import io.swagger.v3.oas.annotations.security.SecurityRequirement;
 import io.swagger.v3.oas.annotations.tags.Tag;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 import javax.servlet.http.HttpServletRequest;
@@ -38,9 +39,12 @@ import org.qortal.crypto.Crypto;
 import org.qortal.data.at.ATData;
 import org.qortal.data.crosschain.CrossChainTradeData;
 import org.qortal.data.crosschain.TradeBotData;
+import org.qortal.data.transaction.MessageTransactionData;
+import org.qortal.data.transaction.TransactionData;
 import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
+import org.qortal.transaction.Transaction;
 import org.qortal.utils.Base58;
 import org.qortal.utils.NTP;
 
@@ -223,6 +227,17 @@ public class CrossChainTradeBotResource {
 			if (crossChainTradeData.mode != AcctMode.OFFERING)
 				throw ApiExceptionFactory.INSTANCE.createException(request, ApiError.INVALID_CRITERIA);
 
+			// Check if there is a buy or a cancel request in progress for this trade
+			List<Transaction.TransactionType> txTypes = List.of(Transaction.TransactionType.MESSAGE);
+			List<TransactionData> unconfirmed = repository.getTransactionRepository().getUnconfirmedTransactions(txTypes, null, 0, 0, false);
+			for (TransactionData  transactionData : unconfirmed) {
+				MessageTransactionData messageTransactionData = (MessageTransactionData) transactionData;
+				if (Objects.equals(messageTransactionData.getRecipient(), atAddress)) {
+					// There is a pending request for this trade, so block this buy attempt to reduce the risk of refunds
+					throw ApiExceptionFactory.INSTANCE.createCustomException(request, ApiError.INVALID_CRITERIA, "Trade has an existing buy request or is pending cancellation.");
+				}
+			}
+
 			AcctTradeBot.ResponseResult result = TradeBot.getInstance().startResponse(repository, atData, acct, crossChainTradeData,
 					tradeBotRespondRequest.foreignKey, tradeBotRespondRequest.receivingAddress);
 

src/main/java/org/qortal/api/websocket/ActiveChatsWebSocket.java

@@ -2,7 +2,9 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
+import java.util.List;
 import java.util.Map;
+import java.util.Objects;
 import java.util.concurrent.atomic.AtomicReference;
 
 import org.eclipse.jetty.websocket.api.Session;
@@ -21,6 +23,8 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @WebSocket
 @SuppressWarnings("serial")
 public class ActiveChatsWebSocket extends ApiWebSocket {
@@ -62,7 +66,9 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 
 	@OnWebSocketMessage
 	public void onWebSocketMessage(Session session, String message) {
-		/* ignored */
+		if (Objects.equals(message, "ping")) {
+			session.getRemote().sendStringByFuture("pong");
+		}
 	}
 
 	private void onNotify(Session session, ChatTransactionData chatTransactionData, String ourAddress, AtomicReference<String> previousOutput) {
@@ -75,7 +81,7 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 		}
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			ActiveChats activeChats = repository.getChatRepository().getActiveChats(ourAddress);
+			ActiveChats activeChats = repository.getChatRepository().getActiveChats(ourAddress, getTargetEncoding(session));
 
 			StringWriter stringWriter = new StringWriter();
 
@@ -93,4 +99,12 @@ public class ActiveChatsWebSocket extends ApiWebSocket {
 		}
 	}
 
+	private Encoding getTargetEncoding(Session session) {
+		// Default to Base58 if not specified, for backwards support
+		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		List<String> encodingList = queryParams.get("encoding");
+		String encoding = (encodingList != null && encodingList.size() == 1) ? encodingList.get(0) : "BASE58";
+		return Encoding.valueOf(encoding);
+	}
+
 }

src/main/java/org/qortal/api/websocket/ChatMessagesWebSocket.java

@@ -2,10 +2,7 @@ package org.qortal.api.websocket;
 
 import java.io.IOException;
 import java.io.StringWriter;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import org.eclipse.jetty.websocket.api.Session;
 import org.eclipse.jetty.websocket.api.WebSocketException;
@@ -22,6 +19,8 @@ import org.qortal.repository.DataException;
 import org.qortal.repository.Repository;
 import org.qortal.repository.RepositoryManager;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @WebSocket
 @SuppressWarnings("serial")
 public class ChatMessagesWebSocket extends ApiWebSocket {
@@ -35,6 +34,16 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 	@Override
 	public void onWebSocketConnect(Session session) {
 		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		Encoding encoding = getTargetEncoding(session);
+
+		List<String> limitList = queryParams.get("limit");
+		Integer limit = (limitList != null && limitList.size() == 1) ? Integer.parseInt(limitList.get(0)) : null;
+
+		List<String> offsetList = queryParams.get("offset");
+		Integer offset = (offsetList != null && offsetList.size() == 1) ? Integer.parseInt(offsetList.get(0)) : null;
+
+		List<String> reverseList = queryParams.get("offset");
+		Boolean reverse = (reverseList != null && reverseList.size() == 1) ? Boolean.getBoolean(reverseList.get(0)) : null;
 
 		List<String> txGroupIds = queryParams.get("txGroupId");
 		if (txGroupIds != null && txGroupIds.size() == 1) {
@@ -47,7 +56,11 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 						txGroupId,
 						null,
 						null,
-						null, null, null);
+						null,
+						null,
+						null,
+						encoding,
+						limit, offset, reverse);
 
 				sendMessages(session, chatMessages);
 			} catch (DataException e) {
@@ -74,8 +87,12 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 					null,
 					null,
 					null,
+					null,
+					null,
 					involvingAddresses,
-					null, null, null);
+					null,
+					encoding,
+					limit, offset, reverse);
 
 			sendMessages(session, chatMessages);
 		} catch (DataException e) {
@@ -101,7 +118,9 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 
 	@OnWebSocketMessage
 	public void onWebSocketMessage(Session session, String message) {
-		/* ignored */
+		if (Objects.equals(message, "ping")) {
+			session.getRemote().sendStringByFuture("pong");
+		}
 	}
 
 	private void onNotify(Session session, ChatTransactionData chatTransactionData, int txGroupId) {
@@ -149,7 +168,7 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 		// Convert ChatTransactionData to ChatMessage
 		ChatMessage chatMessage;
 		try (final Repository repository = RepositoryManager.getRepository()) {
-			chatMessage = repository.getChatRepository().toChatMessage(chatTransactionData);
+			chatMessage = repository.getChatRepository().toChatMessage(chatTransactionData, getTargetEncoding(session));
 		} catch (DataException e) {
 			// No output this time?
 			return;
@@ -158,4 +177,12 @@ public class ChatMessagesWebSocket extends ApiWebSocket {
 		sendMessages(session, Collections.singletonList(chatMessage));
 	}
 
+	private Encoding getTargetEncoding(Session session) {
+		// Default to Base58 if not specified, for backwards support
+		Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
+		List<String> encodingList = queryParams.get("encoding");
+		String encoding = (encodingList != null && encodingList.size() == 1) ? encodingList.get(0) : "BASE58";
+		return Encoding.valueOf(encoding);
+	}
+
 }

src/main/java/org/qortal/arbitrary/ArbitraryDataBuilder.java

@@ -2,6 +2,7 @@ package org.qortal.arbitrary;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.metadata.ArbitraryDataMetadataCache;
 import org.qortal.arbitrary.misc.Service;
@@ -88,7 +89,7 @@ public class ArbitraryDataBuilder {
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.name, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 

src/main/java/org/qortal/arbitrary/ArbitraryDataReader.java

@@ -4,6 +4,7 @@ import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.exception.MissingDataException;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
@@ -59,6 +60,9 @@ public class ArbitraryDataReader {
     private int layerCount;
     private byte[] latestSignature;
 
+    // The resource being read
+    ArbitraryDataResource arbitraryDataResource = null;
+
     public ArbitraryDataReader(String resourceId, ResourceIdType resourceIdType, Service service, String identifier) {
         // Ensure names are always lowercase
         if (resourceIdType == ResourceIdType.NAME) {
@@ -115,6 +119,11 @@ public class ArbitraryDataReader {
         return new ArbitraryDataBuildQueueItem(this.resourceId, this.resourceIdType, this.service, this.identifier);
     }
 
+    private ArbitraryDataResource createArbitraryDataResource() {
+        return new ArbitraryDataResource(this.resourceId, this.resourceIdType, this.service, this.identifier);
+    }
+
+
     /**
      * loadAsynchronously
      *
@@ -162,6 +171,8 @@ public class ArbitraryDataReader {
                 return;
             }
 
+            this.arbitraryDataResource = this.createArbitraryDataResource();
+
             this.preExecute();
             this.deleteExistingFiles();
             this.fetch();
@@ -169,10 +180,18 @@ public class ArbitraryDataReader {
             this.uncompress();
             this.validate();
 
+        } catch (DataNotPublishedException e) {
+            if (e.getMessage() != null) {
+                // Log the message only, to avoid spamming the logs with a full stack trace
+                LOGGER.debug("DataNotPublishedException when trying to load QDN resource: {}", e.getMessage());
+            }
+            this.deleteWorkingDirectory();
+            throw e;
+
         } catch (DataException e) {
             LOGGER.info("DataException when trying to load QDN resource", e);
             this.deleteWorkingDirectory();
-            throw new DataException(e.getMessage());
+            throw e;
 
         } finally {
             this.postExecute();
@@ -427,7 +446,7 @@ public class ArbitraryDataReader {
         byte[] secret = this.secret58 != null ? Base58.decode(this.secret58) : null;
         if (secret != null && secret.length == Transformer.AES256_LENGTH) {
             try {
-                LOGGER.info("Decrypting using algorithm {}...", algorithm);
+                LOGGER.debug("Decrypting {} using algorithm {}...", this.arbitraryDataResource, algorithm);
                 Path unencryptedPath = Paths.get(this.workingPath.toString(), "zipped.zip");
                 SecretKey aesKey = new SecretKeySpec(secret, 0, secret.length, "AES");
                 AES.decryptFile(algorithm, aesKey, this.filePath.toString(), unencryptedPath.toString());
@@ -438,7 +457,7 @@ public class ArbitraryDataReader {
 
             } catch (NoSuchAlgorithmException | InvalidAlgorithmParameterException | NoSuchPaddingException
                     | BadPaddingException | IllegalBlockSizeException | IOException | InvalidKeyException e) {
-                LOGGER.info(String.format("Exception when decrypting using algorithm %s", algorithm), e);
+                LOGGER.info(String.format("Exception when decrypting %s using algorithm %s", this.arbitraryDataResource, algorithm), e);
                 throw new DataException(String.format("Unable to decrypt file at path %s using algorithm %s: %s", this.filePath, algorithm, e.getMessage()));
             }
         } else {

src/main/java/org/qortal/arbitrary/ArbitraryDataResource.java

@@ -3,6 +3,7 @@ package org.qortal.arbitrary;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.ArbitraryDataFile.ResourceIdType;
+import org.qortal.arbitrary.exception.DataNotPublishedException;
 import org.qortal.arbitrary.metadata.ArbitraryDataTransactionMetadata;
 import org.qortal.arbitrary.misc.Service;
 import org.qortal.controller.arbitrary.ArbitraryDataBuildManager;
@@ -325,7 +326,7 @@ public class ArbitraryDataResource {
             if (latestPut == null) {
                 String message = String.format("Couldn't find PUT transaction for name %s, service %s and identifier %s",
                         this.resourceId, this.service, this.identifierString());
-                throw new DataException(message);
+                throw new DataNotPublishedException(message);
             }
             this.latestPutTransaction = latestPut;
 

src/main/java/org/qortal/arbitrary/ArbitraryDataTransactionBuilder.java

@@ -46,6 +46,7 @@ public class ArbitraryDataTransactionBuilder {
     private static final double MAX_FILE_DIFF = 0.5f;
 
     private final String publicKey58;
+    private final long fee;
     private final Path path;
     private final String name;
     private Method method;
@@ -64,11 +65,12 @@ public class ArbitraryDataTransactionBuilder {
     private ArbitraryTransactionData arbitraryTransactionData;
     private ArbitraryDataFile arbitraryDataFile;
 
-    public ArbitraryDataTransactionBuilder(Repository repository, String publicKey58, Path path, String name,
+    public ArbitraryDataTransactionBuilder(Repository repository, String publicKey58, long fee, Path path, String name,
                                            Method method, Service service, String identifier,
                                            String title, String description, List<String> tags, Category category) {
         this.repository = repository;
         this.publicKey58 = publicKey58;
+        this.fee = fee;
         this.path = path;
         this.name = name;
         this.method = method;
@@ -261,7 +263,7 @@ public class ArbitraryDataTransactionBuilder {
             }
 
             final BaseTransactionData baseTransactionData = new BaseTransactionData(now, Group.NO_GROUP,
-                    lastReference, creatorPublicKey, 0L, null);
+                    lastReference, creatorPublicKey, fee, null);
             final int size = (int) arbitraryDataFile.size();
             final int version = 5;
             final int nonce = 0;
@@ -272,7 +274,7 @@ public class ArbitraryDataTransactionBuilder {
             final List<PaymentData> payments = new ArrayList<>();
 
             ArbitraryTransactionData transactionData = new ArbitraryTransactionData(baseTransactionData,
-                    version, service, nonce, size, name, identifier, method,
+                    version, service.value, nonce, size, name, identifier, method,
                     secret, compression, digest, dataType, metadataHash, payments);
 
             this.arbitraryTransactionData = transactionData;

src/main/java/org/qortal/arbitrary/ArbitraryDataWriter.java

@@ -23,16 +23,13 @@ import javax.crypto.NoSuchPaddingException;
 import javax.crypto.SecretKey;
 import java.io.File;
 import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
+import java.nio.file.*;
 import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Objects;
+import java.util.*;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 public class ArbitraryDataWriter {
 
@@ -50,6 +47,7 @@ public class ArbitraryDataWriter {
     private final String description;
     private final List<String> tags;
     private final Category category;
+    private List<String> files;
 
     private int chunkSize = ArbitraryDataFile.CHUNK_SIZE;
 
@@ -80,12 +78,14 @@ public class ArbitraryDataWriter {
         this.description = ArbitraryDataTransactionMetadata.limitDescription(description);
         this.tags = ArbitraryDataTransactionMetadata.limitTags(tags);
         this.category = category;
+        this.files = new ArrayList<>(); // Populated in buildFileList()
     }
 
     public void save() throws IOException, DataException, InterruptedException, MissingDataException {
         try {
             this.preExecute();
             this.validateService();
+            this.buildFileList();
             this.process();
             this.compress();
             this.encrypt();
@@ -143,6 +143,24 @@ public class ArbitraryDataWriter {
         }
     }
 
+    private void buildFileList() throws IOException {
+        // Single file resources consist of a single element in the file list
+        boolean isSingleFile = this.filePath.toFile().isFile();
+        if (isSingleFile) {
+            this.files.add(this.filePath.getFileName().toString());
+            return;
+        }
+
+        // Multi file resources require a walk through the directory tree
+        try (Stream<Path> stream = Files.walk(this.filePath)) {
+            this.files = stream
+                    .filter(Files::isRegularFile)
+                    .map(p -> this.filePath.relativize(p).toString())
+                    .filter(s -> !s.isEmpty())
+                    .collect(Collectors.toList());
+        }
+    }
+
     private void process() throws DataException, IOException, MissingDataException {
         switch (this.method) {
 
@@ -285,6 +303,7 @@ public class ArbitraryDataWriter {
             metadata.setTags(this.tags);
             metadata.setCategory(this.category);
             metadata.setChunks(this.arbitraryDataFile.chunkHashList());
+            metadata.setFiles(this.files);
             metadata.write();
 
             // Create an ArbitraryDataFile from the JSON file (we don't have a signature yet)

src/main/java/org/qortal/arbitrary/exception/DataNotPublishedException.java

@@ -0,0 +1,22 @@
+package org.qortal.arbitrary.exception;
+
+import org.qortal.repository.DataException;
+
+public class DataNotPublishedException extends DataException {
+
+	public DataNotPublishedException() {
+	}
+
+	public DataNotPublishedException(String message) {
+		super(message);
+	}
+
+	public DataNotPublishedException(String message, Throwable cause) {
+		super(message, cause);
+	}
+
+	public DataNotPublishedException(Throwable cause) {
+		super(cause);
+	}
+
+}

src/main/java/org/qortal/arbitrary/metadata/ArbitraryDataTransactionMetadata.java

@@ -19,6 +19,7 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
     private String description;
     private List<String> tags;
     private Category category;
+    private List<String> files;
 
     private static int MAX_TITLE_LENGTH = 80;
     private static int MAX_DESCRIPTION_LENGTH = 500;
@@ -77,6 +78,20 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
             }
             this.chunks = chunksList;
         }
+
+        List<String> filesList = new ArrayList<>();
+        if (metadata.has("files")) {
+            JSONArray files = metadata.getJSONArray("files");
+            if (files != null) {
+                for (int i=0; i<files.length(); i++) {
+                    String tag = files.getString(i);
+                    if (tag != null) {
+                        filesList.add(tag);
+                    }
+                }
+            }
+            this.files = filesList;
+        }
     }
 
     @Override
@@ -111,6 +126,14 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
         }
         outer.put("chunks", chunks);
 
+        JSONArray files = new JSONArray();
+        if (this.files != null) {
+            for (String file : this.files) {
+                files.put(file);
+            }
+        }
+        outer.put("files", files);
+
         this.jsonString = outer.toString(2);
         LOGGER.trace("Transaction metadata: {}", this.jsonString);
     }
@@ -156,6 +179,14 @@ public class ArbitraryDataTransactionMetadata extends ArbitraryDataMetadata {
         return this.category;
     }
 
+    public void setFiles(List<String> files) {
+        this.files = files;
+    }
+
+    public List<String> getFiles() {
+        return this.files;
+    }
+
     public boolean containsChunk(byte[] chunk) {
         for (byte[] c : this.chunks) {
             if (Arrays.equals(c, chunk)) {

src/main/java/org/qortal/arbitrary/misc/Service.java

@@ -10,9 +10,7 @@ import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
+import java.util.*;
 
 import static java.util.Arrays.stream;
 import static java.util.stream.Collectors.toMap;
@@ -20,9 +18,52 @@ import static java.util.stream.Collectors.toMap;
 public enum Service {
     AUTO_UPDATE(1, false, null, null),
     ARBITRARY_DATA(100, false, null, null),
+    QCHAT_ATTACHMENT(120, true, 1024*1024L, null) {
+        @Override
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
+            // Custom validation function to require a single file, with a whitelisted extension
+            int fileCount = 0;
+            File[] files = path.toFile().listFiles();
+            // If already a single file, replace the list with one that contains that file only
+            if (files == null && path.toFile().isFile()) {
+                files = new File[] { path.toFile() };
+            }
+            if (files != null) {
+                for (File file : files) {
+                    if (file.getName().equals(".qortal")) {
+                        continue;
+                    }
+                    if (file.isDirectory()) {
+                        return ValidationResult.DIRECTORIES_NOT_ALLOWED;
+                    }
+                    final String extension = FilenameUtils.getExtension(file.getName()).toLowerCase();
+                    // We must allow blank file extensions because these are used by data published from a plaintext or base64-encoded string
+                    final List<String> allowedExtensions = Arrays.asList("zip", "pdf", "txt", "odt", "ods", "doc", "docx", "xls", "xlsx", "ppt", "pptx", "");
+                    if (extension == null || !allowedExtensions.contains(extension)) {
+                        return ValidationResult.INVALID_FILE_EXTENSION;
+                    }
+                    fileCount++;
+                }
+            }
+            if (fileCount != 1) {
+                return ValidationResult.INVALID_FILE_COUNT;
+            }
+            return ValidationResult.OK;
+        }
+    },
     WEBSITE(200, true, null, null) {
         @Override
-        public ValidationResult validate(Path path) {
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
             // Custom validation function to require an index HTML file in the root directory
             List<String> fileNames = ArbitraryDataRenderer.indexFiles();
             String[] files = path.toFile().list();
@@ -43,6 +84,8 @@ public enum Service {
     QCHAT_IMAGE(420, true, 500*1024L, null),
     VIDEO(500, false, null, null),
     AUDIO(600, false, null, null),
+    QCHAT_AUDIO(610, true, 10*1024*1024L, null),
+    QCHAT_VOICE(620, true, 10*1024*1024L, null),
     BLOG(700, false, null, null),
     BLOG_POST(777, false, null, null),
     BLOG_COMMENT(778, false, null, null),
@@ -53,12 +96,24 @@ public enum Service {
     METADATA(1100, false, null, null),
     GIF_REPOSITORY(1200, true, 25*1024*1024L, null) {
         @Override
-        public ValidationResult validate(Path path) {
+        public ValidationResult validate(Path path) throws IOException {
+            ValidationResult superclassResult = super.validate(path);
+            if (superclassResult != ValidationResult.OK) {
+                return superclassResult;
+            }
+
             // Custom validation function to require .gif files only, and at least 1
             int gifCount = 0;
             File[] files = path.toFile().listFiles();
+            // If already a single file, replace the list with one that contains that file only
+            if (files == null && path.toFile().isFile()) {
+                files = new File[] { path.toFile() };
+            }
             if (files != null) {
                 for (File file : files) {
+                    if (file.getName().equals(".qortal")) {
+                        continue;
+                    }
                     if (file.isDirectory()) {
                         return ValidationResult.DIRECTORIES_NOT_ALLOWED;
                     }
@@ -143,7 +198,8 @@ public enum Service {
         MISSING_INDEX_FILE(4),
         DIRECTORIES_NOT_ALLOWED(5),
         INVALID_FILE_EXTENSION(6),
-        MISSING_DATA(7);
+        MISSING_DATA(7),
+        INVALID_FILE_COUNT(8);
 
         public final int value;
 

src/main/java/org/qortal/block/Block.java

@@ -657,6 +657,10 @@ public class Block {
 		return this.atStates;
 	}
 
+	public byte[] getAtStatesHash() {
+		return this.atStatesHash;
+	}
+
 	/**
 	 * Return expanded info on block's online accounts.
 	 * <p>
@@ -1522,6 +1526,9 @@ public class Block {
 		// Batch update in repository
 		repository.getAccountRepository().modifyMintedBlockCounts(allUniqueExpandedAccounts.stream().map(AccountData::getAddress).collect(Collectors.toList()), +1);
 
+		// Keep track of level bumps in case we need to apply to other entries
+		Map<String, Integer> bumpedAccounts = new HashMap<>();
+
 		// Local changes and also checks for level bump
 		for (AccountData accountData : allUniqueExpandedAccounts) {
 			// Adjust count locally (in Java)
@@ -1535,6 +1542,7 @@ public class Block {
 					if (newLevel > accountData.getLevel()) {
 						// Account has increased in level!
 						accountData.setLevel(newLevel);
+						bumpedAccounts.put(accountData.getAddress(), newLevel);
 						repository.getAccountRepository().setLevel(accountData);
 						LOGGER.trace(() -> String.format("Block minter %s bumped to level %d", accountData.getAddress(), accountData.getLevel()));
 					}
@@ -1542,6 +1550,25 @@ public class Block {
 					break;
 				}
 		}
+
+		// Also bump other entries if need be
+		if (!bumpedAccounts.isEmpty()) {
+			for (ExpandedAccount expandedAccount : expandedAccounts) {
+				Integer newLevel = bumpedAccounts.get(expandedAccount.mintingAccountData.getAddress());
+				if (newLevel != null && expandedAccount.mintingAccountData.getLevel() != newLevel) {
+					expandedAccount.mintingAccountData.setLevel(newLevel);
+					LOGGER.trace("Also bumped {} to level {}", expandedAccount.mintingAccountData.getAddress(), newLevel);
+				}
+
+				if (!expandedAccount.isRecipientAlsoMinter) {
+					newLevel = bumpedAccounts.get(expandedAccount.recipientAccountData.getAddress());
+					if (newLevel != null && expandedAccount.recipientAccountData.getLevel() != newLevel) {
+						expandedAccount.recipientAccountData.setLevel(newLevel);
+						LOGGER.trace("Also bumped {} to level {}", expandedAccount.recipientAccountData.getAddress(), newLevel);
+					}
+				}
+			}
+		}
 	}
 
 	protected void processBlockRewards() throws DataException {

src/main/java/org/qortal/block/BlockChain.java

@@ -76,7 +76,10 @@ public class BlockChain {
 		disableReferenceTimestamp,
 		increaseOnlineAccountsDifficultyTimestamp,
 		onlineAccountMinterLevelValidationHeight,
-		selfSponsorshipAlgoV1Height;
+		selfSponsorshipAlgoV1Height,
+		feeValidationFixTimestamp,
+		chatReferenceTimestamp,
+		arbitraryOptionalFeeTimestamp;
 	}
 
 	// Custom transaction fees
@@ -98,6 +101,13 @@ public class BlockChain {
 	/** Whether only one registered name is allowed per account. */
 	private boolean oneNamePerAccount = false;
 
+	/** Checkpoints */
+	public static class Checkpoint {
+		public int height;
+		public String signature;
+	}
+	private List<Checkpoint> checkpoints;
+
 	/** Block rewards by block height */
 	public static class RewardByHeight {
 		public int height;
@@ -379,6 +389,10 @@ public class BlockChain {
 		return this.oneNamePerAccount;
 	}
 
+	public List<Checkpoint> getCheckpoints() {
+		return this.checkpoints;
+	}
+
 	public List<RewardByHeight> getBlockRewardsByHeight() {
 		return this.rewardsByHeight;
 	}
@@ -501,6 +515,18 @@ public class BlockChain {
 		return this.featureTriggers.get(FeatureTrigger.onlineAccountMinterLevelValidationHeight.name()).intValue();
 	}
 
+	public long getFeeValidationFixTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.feeValidationFixTimestamp.name()).longValue();
+	}
+
+	public long getChatReferenceTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.chatReferenceTimestamp.name()).longValue();
+	}
+
+	public long getArbitraryOptionalFeeTimestamp() {
+		return this.featureTriggers.get(FeatureTrigger.arbitraryOptionalFeeTimestamp.name()).longValue();
+	}
+
 
 	// More complex getters for aspects that change by height or timestamp
 
@@ -669,6 +695,7 @@ public class BlockChain {
 
 		boolean isTopOnly = Settings.getInstance().isTopOnly();
 		boolean archiveEnabled = Settings.getInstance().isArchiveEnabled();
+		boolean isLite = Settings.getInstance().isLite();
 		boolean canBootstrap = Settings.getInstance().getBootstrap();
 		boolean needsArchiveRebuild = false;
 		BlockData chainTip;
@@ -689,22 +716,44 @@ public class BlockChain {
 					}
 				}
 			}
+
+			// Validate checkpoints
+			// Limited to topOnly nodes for now, in order to reduce risk, and to solve a real-world problem with divergent topOnly nodes
+			// TODO: remove the isTopOnly conditional below once this feature has had more testing time
+			if (isTopOnly && !isLite) {
+				List<Checkpoint> checkpoints = BlockChain.getInstance().getCheckpoints();
+				for (Checkpoint checkpoint : checkpoints) {
+					BlockData blockData = repository.getBlockRepository().fromHeight(checkpoint.height);
+					if (blockData == null) {
+						// Try the archive
+						blockData = repository.getBlockArchiveRepository().fromHeight(checkpoint.height);
+					}
+					if (blockData == null) {
+						LOGGER.trace("Couldn't find block for height {}", checkpoint.height);
+						// This is likely due to the block being pruned, so is safe to ignore.
+						// Continue, as there might be other blocks we can check more definitively.
+						continue;
+					}
+
+					byte[] signature = Base58.decode(checkpoint.signature);
+					if (!Arrays.equals(signature, blockData.getSignature())) {
+						LOGGER.info("Error: block at height {} with signature {} doesn't match checkpoint sig: {}. Bootstrapping...", checkpoint.height, Base58.encode(blockData.getSignature()), checkpoint.signature);
+						needsArchiveRebuild = true;
+						break;
+					}
+					LOGGER.info("Block at height {} matches checkpoint signature", blockData.getHeight());
+				}
+			}
+
 		}
 
-		boolean hasBlocks = (chainTip != null && chainTip.getHeight() > 1);
+		// Check first block is Genesis Block
+		if (!isGenesisBlockValid() || needsArchiveRebuild) {
+			try {
+				rebuildBlockchain();
 
-		if (isTopOnly && hasBlocks) {
-			// Top-only mode is enabled and we have blocks, so it's possible that the genesis block has been pruned
-			// It's best not to validate it, and there's no real need to
-		} else {
-			// Check first block is Genesis Block
-			if (!isGenesisBlockValid() || needsArchiveRebuild) {
-				try {
-					rebuildBlockchain();
-
-				} catch (InterruptedException e) {
-					throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
-				}
+			} catch (InterruptedException e) {
+				throw new DataException(String.format("Interrupted when trying to rebuild blockchain: %s", e.getMessage()));
 			}
 		}
 
@@ -713,9 +762,7 @@ public class BlockChain {
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			repository.checkConsistency();
 
-			// Set the number of blocks to validate based on the pruned state of the chain
-			// If pruned, subtract an extra 10 to allow room for error
-			int blocksToValidate = (isTopOnly || archiveEnabled) ? Settings.getInstance().getPruneBlockLimit() - 10 : 1440;
+			int blocksToValidate = Math.min(Settings.getInstance().getPruneBlockLimit() - 10, 1440);
 
 			int startHeight = Math.max(repository.getBlockRepository().getBlockchainHeight() - blocksToValidate, 1);
 			BlockData detachedBlockData = repository.getBlockRepository().getDetachedBlockSignature(startHeight);

src/main/java/org/qortal/controller/BlockMinter.java

@@ -63,8 +63,8 @@ public class BlockMinter extends Thread {
 	public void run() {
 		Thread.currentThread().setName("BlockMinter");
 
-		if (Settings.getInstance().isLite()) {
-			// Lite nodes do not mint
+		if (Settings.getInstance().isTopOnly() || Settings.getInstance().isLite()) {
+			// Top only and lite nodes do not sign blocks
 			return;
 		}
 		if (Settings.getInstance().getWipeUnconfirmedOnStart()) {

src/main/java/org/qortal/controller/Controller.java

@@ -400,12 +400,8 @@ public class Controller extends Thread {
 			RepositoryFactory repositoryFactory = new HSQLDBRepositoryFactory(getRepositoryUrl());
 			RepositoryManager.setRepositoryFactory(repositoryFactory);
 			RepositoryManager.setRequestedCheckpoint(Boolean.TRUE);
-
-			try (final Repository repository = RepositoryManager.getRepository()) {
-				RepositoryManager.archive(repository);
-				RepositoryManager.prune(repository);
-			}
-		} catch (DataException e) {
+		}
+		catch (DataException e) {
 			// If exception has no cause then repository is in use by some other process.
 			if (e.getCause() == null) {
 				LOGGER.info("Repository in use by another process?");
@@ -769,6 +765,16 @@ public class Controller extends Thread {
 		}
 	};
 
+	public static final Predicate<Peer> wasRecentlyTooDivergent = peer -> {
+		Long now = NTP.getTime();
+		Long peerLastTooDivergentTime = peer.getLastTooDivergentTime();
+		if (now == null || peerLastTooDivergentTime == null)
+			return false;
+
+		// Exclude any peers that were TOO_DIVERGENT in the last 5 mins
+		return (now - peerLastTooDivergentTime < 5 * 60 * 1000L);
+	};
+
 	private long getRandomRepositoryMaintenanceInterval() {
 		final long minInterval = Settings.getInstance().getRepositoryMaintenanceMinInterval();
 		final long maxInterval = Settings.getInstance().getRepositoryMaintenanceMaxInterval();
@@ -1369,9 +1375,24 @@ public class Controller extends Thread {
 			// If we have no block data, we should check the archive in case it's there
 			if (blockData == null) {
 				if (Settings.getInstance().isArchiveEnabled()) {
-					byte[] bytes = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, true, repository);
-					if (bytes != null) {
-						CachedBlockMessage blockMessage = new CachedBlockMessage(bytes);
+					Triple<byte[], Integer, Integer> serializedBlock = BlockArchiveReader.getInstance().fetchSerializedBlockBytesForSignature(signature, true, repository);
+					if (serializedBlock != null) {
+						byte[] bytes = serializedBlock.getA();
+						Integer serializationVersion = serializedBlock.getB();
+
+						Message blockMessage;
+						switch (serializationVersion) {
+							case 1:
+								blockMessage = new CachedBlockMessage(bytes);
+								break;
+
+							case 2:
+								blockMessage = new CachedBlockV2Message(bytes);
+								break;
+
+							default:
+								return;
+						}
 						blockMessage.setId(message.getId());
 
 						// This call also causes the other needed data to be pulled in from repository

src/main/java/org/qortal/controller/PirateChainWalletController.java

@@ -163,7 +163,7 @@ public class PirateChainWalletController extends Thread {
 
             // Library not found, so check if we've fetched the resource from QDN
             ArbitraryTransactionData t = this.getTransactionData(repository);
-            if (t == null) {
+            if (t == null || t.getService() == null) {
                 // Can't find the transaction - maybe on a different chain?
                 return;
             }

src/main/java/org/qortal/controller/Synchronizer.java

@@ -1121,6 +1121,7 @@ public class Synchronizer extends Thread {
 			// If common block is too far behind us then we're on massively different forks so give up.
 			if (!force && testHeight < ourHeight - MAXIMUM_COMMON_DELTA) {
 				LOGGER.info(String.format("Blockchain too divergent with peer %s", peer));
+				peer.setLastTooDivergentTime(NTP.getTime());
 				return SynchronizationResult.TOO_DIVERGENT;
 			}
 
@@ -1130,6 +1131,9 @@ public class Synchronizer extends Thread {
 			testHeight = Math.max(testHeight - step, 1);
 		}
 
+		// Peer not considered too divergent
+		peer.setLastTooDivergentTime(0L);
+
 		// Prepend test block's summary as first block summary, as summaries returned are *after* test block
 		BlockSummaryData testBlockSummary = new BlockSummaryData(testBlockData);
 		blockSummariesFromCommon.add(0, testBlockSummary);

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataCleanupManager.java

@@ -137,7 +137,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 						// Fetch the transaction data
 						ArbitraryTransactionData arbitraryTransactionData = ArbitraryTransactionUtils.fetchTransactionData(repository, signature);
-						if (arbitraryTransactionData == null) {
+						if (arbitraryTransactionData == null || arbitraryTransactionData.getService() == null) {
 							continue;
 						}
 
@@ -204,7 +204,7 @@ public class ArbitraryDataCleanupManager extends Thread {
 
 						if (completeFileExists && !allChunksExist) {
 							// We have the complete file but not the chunks, so let's convert it
-							LOGGER.info(String.format("Transaction %s has complete file but no chunks",
+							LOGGER.debug(String.format("Transaction %s has complete file but no chunks",
 									Base58.encode(arbitraryTransactionData.getSignature())));
 
 							ArbitraryTransactionUtils.convertFileToChunks(arbitraryTransactionData, now, STALE_FILE_TIMEOUT);

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataFileManager.java

@@ -82,7 +82,7 @@ public class ArbitraryDataFileManager extends Thread {
 
         try {
             // Use a fixed thread pool to execute the arbitrary data file requests
-            int threadCount = 10;
+            int threadCount = 5;
             ExecutorService arbitraryDataFileRequestExecutor = Executors.newFixedThreadPool(threadCount);
             for (int i = 0; i < threadCount; i++) {
                 arbitraryDataFileRequestExecutor.execute(new ArbitraryDataFileRequestThread());
@@ -288,7 +288,7 @@ public class ArbitraryDataFileManager extends Thread {
         // The ID needs to match that of the original request
         message.setId(originalMessage.getId());
 
-        if (!requestingPeer.sendMessage(message)) {
+        if (!requestingPeer.sendMessageWithTimeout(message, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
             LOGGER.debug("Failed to forward arbitrary data file to peer {}", requestingPeer);
             requestingPeer.disconnect("failed to forward arbitrary data file");
         }
@@ -564,13 +564,16 @@ public class ArbitraryDataFileManager extends Thread {
                 LOGGER.trace("Hash {} exists", hash58);
 
                 // We can serve the file directly as we already have it
+                LOGGER.debug("Sending file {}...", arbitraryDataFile);
                 ArbitraryDataFileMessage arbitraryDataFileMessage = new ArbitraryDataFileMessage(signature, arbitraryDataFile);
                 arbitraryDataFileMessage.setId(message.getId());
-                if (!peer.sendMessage(arbitraryDataFileMessage)) {
-                    LOGGER.debug("Couldn't sent file");
+                if (!peer.sendMessageWithTimeout(arbitraryDataFileMessage, (int) ArbitraryDataManager.ARBITRARY_REQUEST_TIMEOUT)) {
+                    LOGGER.debug("Couldn't send file {}", arbitraryDataFile);
                     peer.disconnect("failed to send file");
                 }
-                LOGGER.debug("Sent file {}", arbitraryDataFile);
+                else {
+                    LOGGER.debug("Sent file {}", arbitraryDataFile);
+                }
             }
             else if (relayInfo != null) {
                 LOGGER.debug("We have relay info for hash {}", Base58.encode(hash));

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataManager.java

@@ -398,6 +398,11 @@ public class ArbitraryDataManager extends Thread {
 	// Entrypoint to request new metadata from peers
 	public ArbitraryDataTransactionMetadata fetchMetadata(ArbitraryTransactionData arbitraryTransactionData) {
 
+		if (arbitraryTransactionData.getService() == null) {
+			// Can't fetch metadata without a valid service
+			return null;
+		}
+
 		ArbitraryDataResource resource = new ArbitraryDataResource(
 				arbitraryTransactionData.getName(),
 				ArbitraryDataFile.ResourceIdType.NAME,
@@ -489,7 +494,7 @@ public class ArbitraryDataManager extends Thread {
 	public void invalidateCache(ArbitraryTransactionData arbitraryTransactionData) {
 		String signature58 = Base58.encode(arbitraryTransactionData.getSignature());
 
-		if (arbitraryTransactionData.getName() != null) {
+		if (arbitraryTransactionData.getName() != null && arbitraryTransactionData.getService() != null) {
 			String resourceId = arbitraryTransactionData.getName().toLowerCase();
 			Service service = arbitraryTransactionData.getService();
 			String identifier = arbitraryTransactionData.getIdentifier();

src/main/java/org/qortal/controller/arbitrary/ArbitraryDataStorageManager.java

@@ -48,7 +48,6 @@ public class ArbitraryDataStorageManager extends Thread {
     private List<ArbitraryTransactionData> hostedTransactions;
 
     private String searchQuery;
-    private List<ArbitraryTransactionData> searchResultsTransactions;
 
     private static final long DIRECTORY_SIZE_CHECK_INTERVAL = 10 * 60 * 1000L; // 10 minutes
 
@@ -344,11 +343,6 @@ public class ArbitraryDataStorageManager extends Thread {
      */
 
     public List<ArbitraryTransactionData> searchHostedTransactions(Repository repository, String query, Integer limit, Integer offset) {
-        // Load from results cache if we can (results that exists for the same query), to avoid disk reads
-        if (this.searchResultsTransactions != null && this.searchQuery.equals(query.toLowerCase())) {
-            return ArbitraryTransactionUtils.limitOffsetTransactions(this.searchResultsTransactions, limit, offset);
-        }
-
         // Using cache if we can, to avoid disk reads
         if (this.hostedTransactions == null) {
             this.hostedTransactions = this.loadAllHostedTransactions(repository);
@@ -376,10 +370,7 @@ public class ArbitraryDataStorageManager extends Thread {
         // Sort by newest first
         searchResultsList.sort(Comparator.comparingLong(ArbitraryTransactionData::getTimestamp).reversed());
 
-        // Update cache
-        this.searchResultsTransactions = searchResultsList;
-
-        return ArbitraryTransactionUtils.limitOffsetTransactions(this.searchResultsTransactions, limit, offset);
+        return ArbitraryTransactionUtils.limitOffsetTransactions(searchResultsList, limit, offset);
     }
 
     /**

src/main/java/org/qortal/controller/repository/AtStatesPruner.java

@@ -39,9 +39,11 @@ public class AtStatesPruner implements Runnable {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int pruneStartHeight = repository.getATRepository().getAtPruneHeight();
+			int maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
 
 			repository.discardChanges();
-			repository.getATRepository().rebuildLatestAtStates();
+			repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
+			repository.saveChanges();
 
 			while (!Controller.isStopping()) {
 				repository.discardChanges();
@@ -91,7 +93,8 @@ public class AtStatesPruner implements Runnable {
 					if (upperPrunableHeight > upperBatchHeight) {
 						pruneStartHeight = upperBatchHeight;
 						repository.getATRepository().setAtPruneHeight(pruneStartHeight);
-						repository.getATRepository().rebuildLatestAtStates();
+						maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
+						repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
 						repository.saveChanges();
 
 						final int finalPruneStartHeight = pruneStartHeight;

src/main/java/org/qortal/controller/repository/AtStatesTrimmer.java

@@ -26,9 +26,11 @@ public class AtStatesTrimmer implements Runnable {
 
 		try (final Repository repository = RepositoryManager.getRepository()) {
 			int trimStartHeight = repository.getATRepository().getAtTrimHeight();
+			int maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
 
 			repository.discardChanges();
-			repository.getATRepository().rebuildLatestAtStates();
+			repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
+			repository.saveChanges();
 
 			while (!Controller.isStopping()) {
 				repository.discardChanges();
@@ -69,7 +71,8 @@ public class AtStatesTrimmer implements Runnable {
 					if (upperTrimmableHeight > upperBatchHeight) {
 						trimStartHeight = upperBatchHeight;
 						repository.getATRepository().setAtTrimHeight(trimStartHeight);
-						repository.getATRepository().rebuildLatestAtStates();
+						maxLatestAtStatesHeight = PruneManager.getMaxHeightForLatestAtStates(repository);
+						repository.getATRepository().rebuildLatestAtStates(maxLatestAtStatesHeight);
 						repository.saveChanges();
 
 						final int finalTrimStartHeight = trimStartHeight;

src/main/java/org/qortal/controller/repository/BlockArchiveRebuilder.java

@@ -0,0 +1,121 @@
+package org.qortal.controller.repository;
+
+import org.apache.commons.io.FileUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.qortal.controller.Controller;
+import org.qortal.controller.Synchronizer;
+import org.qortal.repository.*;
+import org.qortal.settings.Settings;
+import org.qortal.transform.TransformationException;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+
+public class BlockArchiveRebuilder {
+
+    private static final Logger LOGGER = LogManager.getLogger(BlockArchiveRebuilder.class);
+
+    private final int serializationVersion;
+
+    public BlockArchiveRebuilder(int serializationVersion) {
+        this.serializationVersion = serializationVersion;
+    }
+
+    public void start() throws DataException, IOException {
+        if (!Settings.getInstance().isArchiveEnabled() || Settings.getInstance().isLite()) {
+            return;
+        }
+
+        // New archive path is in a different location from original archive path, to avoid conflicts.
+        // It will be moved later, once the process is complete.
+        final Path newArchivePath = Paths.get(Settings.getInstance().getRepositoryPath(), "archive-rebuild");
+        final Path originalArchivePath = Paths.get(Settings.getInstance().getRepositoryPath(), "archive");
+
+        // Delete archive-rebuild if it exists from a previous attempt
+        FileUtils.deleteDirectory(newArchivePath.toFile());
+
+        try (final Repository repository = RepositoryManager.getRepository()) {
+            int startHeight = 1; // We need to rebuild the entire archive
+
+            LOGGER.info("Rebuilding block archive from height {}...", startHeight);
+
+            while (!Controller.isStopping()) {
+                repository.discardChanges();
+
+                Thread.sleep(1000L);
+
+                // Don't even attempt if we're mid-sync as our repository requests will be delayed for ages
+                if (Synchronizer.getInstance().isSynchronizing()) {
+                    continue;
+                }
+
+                // Rebuild archive
+                try {
+                    final int maximumArchiveHeight = BlockArchiveReader.getInstance().getHeightOfLastArchivedBlock();
+                    if (startHeight >= maximumArchiveHeight) {
+                        // We've finished.
+                        // Delete existing archive and move the newly built one into its place
+                        FileUtils.deleteDirectory(originalArchivePath.toFile());
+                        FileUtils.moveDirectory(newArchivePath.toFile(), originalArchivePath.toFile());
+                        BlockArchiveReader.getInstance().invalidateFileListCache();
+                        LOGGER.info("Block archive successfully rebuilt");
+                        return;
+                    }
+
+                    BlockArchiveWriter writer = new BlockArchiveWriter(startHeight, maximumArchiveHeight, serializationVersion, newArchivePath, repository);
+
+                    // Set data source to BLOCK_ARCHIVE as we are rebuilding
+                    writer.setDataSource(BlockArchiveWriter.BlockArchiveDataSource.BLOCK_ARCHIVE);
+
+                    // We can't enforce the 100MB file size target, as the final file needs to contain all blocks
+                    // that exist in the current archive. Otherwise, the final blocks in the archive will be lost.
+                    writer.setShouldEnforceFileSizeTarget(false);
+
+                    // We want to log the rebuild progress
+                    writer.setShouldLogProgress(true);
+
+                    BlockArchiveWriter.BlockArchiveWriteResult result = writer.write();
+                    switch (result) {
+                        case OK:
+                            // Increment block archive height
+                            startHeight += writer.getWrittenCount();
+                            repository.saveChanges();
+                            break;
+
+                        case STOPPING:
+                            return;
+
+                        // We've reached the limit of the blocks we can archive
+                        // Sleep for a while to allow more to become available
+                        case NOT_ENOUGH_BLOCKS:
+                            // This shouldn't happen, as we're not enforcing minimum file sizes
+                            repository.discardChanges();
+                            throw new DataException("Unable to rebuild archive due to unexpected NOT_ENOUGH_BLOCKS response.");
+
+                        case BLOCK_NOT_FOUND:
+                            // We tried to archive a block that didn't exist. This is a major failure and likely means
+                            // that a bootstrap or re-sync is needed. Try again every minute until then.
+                            LOGGER.info("Error: block not found when rebuilding archive. If this error persists, " +
+                                    "a bootstrap or re-sync may be needed.");
+                            repository.discardChanges();
+                            throw new DataException("Unable to rebuild archive because a block is missing.");
+                    }
+
+                } catch (IOException | TransformationException e) {
+                    LOGGER.info("Caught exception when rebuilding block archive", e);
+                    throw new DataException("Unable to rebuild block archive");
+                }
+
+            }
+        } catch (InterruptedException e) {
+            // Do nothing
+        } finally {
+            // Delete archive-rebuild if it still exists, as that means something went wrong
+            FileUtils.deleteDirectory(newArchivePath.toFile());
+        }
+    }
+
+}

src/main/java/org/qortal/controller/repository/NamesDatabaseIntegrityCheck.java

@@ -102,6 +102,21 @@ public class NamesDatabaseIntegrityCheck {
                     }
                 }
 
+                // Process CANCEL_SELL_NAME transactions
+                if (currentTransaction.getType() == TransactionType.CANCEL_SELL_NAME) {
+                    CancelSellNameTransactionData cancelSellNameTransactionData = (CancelSellNameTransactionData) currentTransaction;
+                    Name nameObj = new Name(repository, cancelSellNameTransactionData.getName());
+                    if (nameObj != null && nameObj.getNameData() != null) {
+                        nameObj.cancelSell(cancelSellNameTransactionData);
+                        modificationCount++;
+                        LOGGER.trace("Processed CANCEL_SELL_NAME transaction for name {}", name);
+                    }
+                    else {
+                        // Something went wrong
+                        throw new DataException(String.format("Name data not found for name %s", cancelSellNameTransactionData.getName()));
+                    }
+                }
+
                 // Process BUY_NAME transactions
                 if (currentTransaction.getType() == TransactionType.BUY_NAME) {
                     BuyNameTransactionData buyNameTransactionData = (BuyNameTransactionData) currentTransaction;
@@ -128,7 +143,7 @@ public class NamesDatabaseIntegrityCheck {
     public int rebuildAllNames() {
         int modificationCount = 0;
         try (final Repository repository = RepositoryManager.getRepository()) {
-            List<String> names = this.fetchAllNames(repository);
+            List<String> names = this.fetchAllNames(repository); // TODO: de-duplicate, to speed up this process
             for (String name : names) {
                 modificationCount += this.rebuildName(name, repository);
             }
@@ -326,6 +341,10 @@ public class NamesDatabaseIntegrityCheck {
                 TransactionType.BUY_NAME, Arrays.asList("name = ?"), Arrays.asList(name));
         signatures.addAll(buyNameTransactions);
 
+        List<byte[]> cancelSellNameTransactions = repository.getTransactionRepository().getSignaturesMatchingCustomCriteria(
+                TransactionType.CANCEL_SELL_NAME, Arrays.asList("name = ?"), Arrays.asList(name));
+        signatures.addAll(cancelSellNameTransactions);
+
         List<TransactionData> transactions = new ArrayList<>();
         for (byte[] signature : signatures) {
             TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
@@ -390,6 +409,12 @@ public class NamesDatabaseIntegrityCheck {
                     names.add(sellNameTransactionData.getName());
                 }
             }
+            if ((transactionData instanceof CancelSellNameTransactionData)) {
+                CancelSellNameTransactionData cancelSellNameTransactionData = (CancelSellNameTransactionData) transactionData;
+                if (!names.contains(cancelSellNameTransactionData.getName())) {
+                    names.add(cancelSellNameTransactionData.getName());
+                }
+            }
         }
         return names;
     }

src/main/java/org/qortal/controller/repository/PruneManager.java

@@ -157,4 +157,18 @@ public class PruneManager {
         return (height < latestUnprunedHeight);
     }
 
+    /**
+     * When rebuilding the latest AT states, we need to specify a maxHeight, so that we aren't tracking
+     * very recent AT states that could potentially be orphaned. This method ensures that AT states
+     * are given a sufficient number of blocks to confirm before being tracked as a latest AT state.
+     */
+    public static int getMaxHeightForLatestAtStates(Repository repository) throws DataException {
+        // Get current chain height, and subtract a certain number of "confirmation" blocks
+        // This is to ensure we are basing our latest AT states data on confirmed blocks -
+        // ones that won't be orphaned in any normal circumstances
+        final int confirmationBlocks = 250;
+        final int chainHeight = repository.getBlockRepository().getBlockchainHeight();
+        return chainHeight - confirmationBlocks;
+    }
+
 }

src/main/java/org/qortal/crosschain/Bitcoin.java

@@ -49,6 +49,7 @@ public class Bitcoin extends Bitcoiny {
 						//CLOSED new Server("bitcoin.grey.pw", Server.ConnectionType.SSL, 50002),
 						//CLOSED new Server("btc.litepay.ch", Server.ConnectionType.SSL, 50002),
 						//CLOSED new Server("electrum.pabu.io", Server.ConnectionType.SSL, 50002),
+						//CLOSED new Server("electrumx.dev", Server.ConnectionType.SSL, 50002),
 						//CLOSED new Server("electrumx.hodlwallet.com", Server.ConnectionType.SSL, 50002),
 						//CLOSED new Server("gd42.org", Server.ConnectionType.SSL, 50002),
 						//CLOSED new Server("korea.electrum-server.com", Server.ConnectionType.SSL, 50002),
@@ -56,28 +57,75 @@ public class Bitcoin extends Bitcoiny {
 						//1.15.0 new Server("alviss.coinjoined.com", Server.ConnectionType.SSL, 50002),
 						//1.15.0 new Server("electrum.acinq.co", Server.ConnectionType.SSL, 50002),
 						//1.14.0 new Server("electrum.coinext.com.br", Server.ConnectionType.SSL, 50002),
+						//F1.7.0 new Server("btc.lastingcoin.net", Server.ConnectionType.SSL, 50002),
 						new Server("104.248.139.211", Server.ConnectionType.SSL, 50002),
+						new Server("128.0.190.26", Server.ConnectionType.SSL, 50002),
 						new Server("142.93.6.38", Server.ConnectionType.SSL, 50002),
 						new Server("157.245.172.236", Server.ConnectionType.SSL, 50002),
 						new Server("167.172.226.175", Server.ConnectionType.SSL, 50002),
 						new Server("167.172.42.31", Server.ConnectionType.SSL, 50002),
 						new Server("178.62.80.20", Server.ConnectionType.SSL, 50002),
 						new Server("185.64.116.15", Server.ConnectionType.SSL, 50002),
+						new Server("188.165.206.215", Server.ConnectionType.SSL, 50002),
+						new Server("188.165.211.112", Server.ConnectionType.SSL, 50002),
+						new Server("2azzarita.hopto.org", Server.ConnectionType.SSL, 50002),
+						new Server("2electrumx.hopto.me", Server.ConnectionType.SSL, 56022),
+						new Server("2ex.digitaleveryware.com", Server.ConnectionType.SSL, 50002),
+						new Server("65.39.140.37", Server.ConnectionType.SSL, 50002),
 						new Server("68.183.188.105", Server.ConnectionType.SSL, 50002),
+						new Server("71.73.14.254", Server.ConnectionType.SSL, 50002),
+						new Server("94.23.247.135", Server.ConnectionType.SSL, 50002),
+						new Server("assuredly.not.fyi", Server.ConnectionType.SSL, 50002),
+						new Server("ax101.blockeng.ch", Server.ConnectionType.SSL, 50002),
+						new Server("ax102.blockeng.ch", Server.ConnectionType.SSL, 50002),
+						new Server("b.1209k.com", Server.ConnectionType.SSL, 50002),
+						new Server("b6.1209k.com", Server.ConnectionType.SSL, 50002),
+						new Server("bitcoin.dermichi.com", Server.ConnectionType.SSL, 50002),
+						new Server("bitcoin.lu.ke", Server.ConnectionType.SSL, 50002),
 						new Server("bitcoin.lukechilds.co", Server.ConnectionType.SSL, 50002),
 						new Server("blkhub.net", Server.ConnectionType.SSL, 50002),
-						new Server("btc.lastingcoin.net", Server.ConnectionType.SSL, 50002),
+						new Server("btc.electroncash.dk", Server.ConnectionType.SSL, 60002),
+						new Server("btc.ocf.sh", Server.ConnectionType.SSL, 50002),
 						new Server("btce.iiiiiii.biz", Server.ConnectionType.SSL, 50002),
 						new Server("caleb.vegas", Server.ConnectionType.SSL, 50002),
 						new Server("eai.coincited.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.bhoovd.com", Server.ConnectionType.SSL, 50002),
 						new Server("electrum.bitaroo.net", Server.ConnectionType.SSL, 50002),
-						new Server("electrumx.dev", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.bitcoinlizard.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.blockstream.info", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.emzy.de", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.exan.tech", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.kendigisland.xyz", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.mmitech.info", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.petrkr.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.stippy.com", Server.ConnectionType.SSL, 50002),
+						new Server("electrum.thomasfischbach.de", Server.ConnectionType.SSL, 50002),
+						new Server("electrum0.snel.it", Server.ConnectionType.SSL, 50002),
+						new Server("electrum1.cipig.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum2.cipig.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrum3.cipig.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrumx.alexridevski.net", Server.ConnectionType.SSL, 50002),
+						new Server("electrumx-core.1209k.com", Server.ConnectionType.SSL, 50002),
 						new Server("elx.bitske.com", Server.ConnectionType.SSL, 50002),
+						new Server("ex03.axalgo.com", Server.ConnectionType.SSL, 50002),
+						new Server("ex05.axalgo.com", Server.ConnectionType.SSL, 50002),
+						new Server("ex07.axalgo.com", Server.ConnectionType.SSL, 50002),
 						new Server("fortress.qtornado.com", Server.ConnectionType.SSL, 50002),
+						new Server("fulcrum.grey.pw", Server.ConnectionType.SSL, 50002),
+						new Server("fulcrum.sethforprivacy.com", Server.ConnectionType.SSL, 51002),
 						new Server("guichet.centure.cc", Server.ConnectionType.SSL, 50002),
-						new Server("kareoke.qoppa.org", Server.ConnectionType.SSL, 50002),
 						new Server("hodlers.beer", Server.ConnectionType.SSL, 50002),
+						new Server("kareoke.qoppa.org", Server.ConnectionType.SSL, 50002),
+						new Server("kirsche.emzy.de", Server.ConnectionType.SSL, 50002),
 						new Server("node1.btccuracao.com", Server.ConnectionType.SSL, 50002),
+						new Server("osr1ex1.compumundohipermegared.one", Server.ConnectionType.SSL, 50002),
+						new Server("smmalis37.ddns.net", Server.ConnectionType.SSL, 50002),
+						new Server("ulrichard.ch", Server.ConnectionType.SSL, 50002),
+						new Server("vmd104012.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("vmd104014.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("vmd63185.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("vmd71287.contaboserver.net", Server.ConnectionType.SSL, 50002),
+						new Server("vmd84592.contaboserver.net", Server.ConnectionType.SSL, 50002),
 						new Server("xtrum.com", Server.ConnectionType.SSL, 50002));
 			}
 

src/main/java/org/qortal/crosschain/Bitcoiny.java

@@ -167,6 +167,16 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 		return blockTimestamps.get(5);
 	}
 
+	/**
+	 * Returns height from latest block.
+	 * <p>
+	 * @throws ForeignBlockchainException if error occurs
+	 */
+	public int getBlockchainHeight() throws ForeignBlockchainException {
+		int height = this.blockchainProvider.getCurrentHeight();
+		return height;
+	}
+
 	/** Returns fee per transaction KB. To be overridden for testnet/regtest. */
 	public Coin getFeePerKb() {
 		return this.bitcoinjContext.getFeePerKb();
@@ -357,19 +367,33 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 	 * @return unspent BTC balance, or null if unable to determine balance
 	 */
 	public Long getWalletBalance(String key58) throws ForeignBlockchainException {
-		// It's more accurate to calculate the balance from the transactions, rather than asking Bitcoinj
-		return this.getWalletBalanceFromTransactions(key58);
+		Long balance = 0L;
 
-//		Context.propagate(bitcoinjContext);
-//
-//		Wallet wallet = walletFromDeterministicKey58(key58);
-//		wallet.setUTXOProvider(new WalletAwareUTXOProvider(this, wallet));
-//
-//		Coin balance = wallet.getBalance();
-//		if (balance == null)
-//			return null;
-//
-//		return balance.value;
+		List<TransactionOutput> allUnspentOutputs = new ArrayList<>();
+		Set<String> walletAddresses = this.getWalletAddresses(key58);
+		for (String address : walletAddresses) {
+			allUnspentOutputs.addAll(this.getUnspentOutputs(address));
+		}
+		for (TransactionOutput output : allUnspentOutputs) {
+			if (!output.isAvailableForSpending()) {
+				continue;
+			}
+			balance += output.getValue().value;
+		}
+		return balance;
+	}
+
+	public Long getWalletBalanceFromBitcoinj(String key58) {
+		Context.propagate(bitcoinjContext);
+
+		Wallet wallet = walletFromDeterministicKey58(key58);
+		wallet.setUTXOProvider(new WalletAwareUTXOProvider(this, wallet));
+
+		Coin balance = wallet.getBalance();
+		if (balance == null)
+			return null;
+
+		return balance.value;
 	}
 
 	public Long getWalletBalanceFromTransactions(String key58) throws ForeignBlockchainException {
@@ -464,6 +488,64 @@ public abstract class Bitcoiny implements ForeignBlockchain {
 		}
 	}
 
+	public Set<String> getWalletAddresses(String key58) throws ForeignBlockchainException {
+		synchronized (this) {
+			Context.propagate(bitcoinjContext);
+
+			Wallet wallet = walletFromDeterministicKey58(key58);
+			DeterministicKeyChain keyChain = wallet.getActiveKeyChain();
+
+			keyChain.setLookaheadSize(Bitcoiny.WALLET_KEY_LOOKAHEAD_INCREMENT);
+			keyChain.maybeLookAhead();
+
+			List<DeterministicKey> keys = new ArrayList<>(keyChain.getLeafKeys());
+
+			Set<String> keySet = new HashSet<>();
+
+			int unusedCounter = 0;
+			int ki = 0;
+			do {
+				boolean areAllKeysUnused = true;
+
+				for (; ki < keys.size(); ++ki) {
+					DeterministicKey dKey = keys.get(ki);
+
+					// Check for transactions
+					Address address = Address.fromKey(this.params, dKey, ScriptType.P2PKH);
+					keySet.add(address.toString());
+					byte[] script = ScriptBuilder.createOutputScript(address).getProgram();
+
+					// Ask for transaction history - if it's empty then key has never been used
+					List<TransactionHash> historicTransactionHashes = this.getAddressTransactions(script, false);
+
+					if (!historicTransactionHashes.isEmpty()) {
+						areAllKeysUnused = false;
+					}
+				}
+
+				if (areAllKeysUnused) {
+					// No transactions
+					if (unusedCounter >= Settings.getInstance().getGapLimit()) {
+						// ... and we've hit our search limit
+						break;
+					}
+					// We haven't hit our search limit yet so increment the counter and keep looking
+					unusedCounter += WALLET_KEY_LOOKAHEAD_INCREMENT;
+				} else {
+					// Some keys in this batch were used, so reset the counter
+					unusedCounter = 0;
+				}
+
+				// Generate some more keys
+				keys.addAll(generateMoreKeys(keyChain));
+
+				// Process new keys
+			} while (true);
+
+			return keySet;
+		}
+	}
+
 	protected SimpleTransaction convertToSimpleTransaction(BitcoinyTransaction t, Set<String> keySet) {
 		long amount = 0;
 		long total = 0L;

src/main/java/org/qortal/crosschain/Digibyte.java

@@ -45,6 +45,9 @@ public class Digibyte extends Bitcoiny {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
 						// Status verified at https://1209k.com/bitcoin-eye/ele.php?chain=dgb
+						new Server("electrum.qortal.link", Server.ConnectionType.SSL, 55002),
+						new Server("electrum-dgb.qortal.online", ConnectionType.SSL, 50002),
+						new Server("electrum1-dgb.qortal.online", ConnectionType.SSL, 50002),
 						new Server("electrum1.cipig.net", ConnectionType.SSL, 20059),
 						new Server("electrum2.cipig.net", ConnectionType.SSL, 20059),
 						new Server("electrum3.cipig.net", ConnectionType.SSL, 20059));
@@ -134,6 +137,8 @@ public class Digibyte extends Bitcoiny {
 			Context bitcoinjContext = new Context(digibyteNet.getParams());
 
 			instance = new Digibyte(digibyteNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/crosschain/Dogecoin.java

@@ -45,10 +45,13 @@ public class Dogecoin extends Bitcoiny {
 			public Collection<Server> getServers() {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
+						// Status verified at https://1209k.com/bitcoin-eye/ele.php?chain=doge
+						new Server("electrum.qortal.link", Server.ConnectionType.SSL, 54002),
+						new Server("electrum-doge.qortal.online", ConnectionType.SSL, 50002),
+						new Server("electrum1-doge.qortal.online", ConnectionType.SSL, 50002),
 						new Server("electrum1.cipig.net", ConnectionType.SSL, 20060),
 						new Server("electrum2.cipig.net", ConnectionType.SSL, 20060),
 						new Server("electrum3.cipig.net", ConnectionType.SSL, 20060));
-						// TODO: add more mainnet servers. It's too centralized.
 			}
 
 			@Override

src/main/java/org/qortal/crosschain/ElectrumX.java

@@ -5,6 +5,7 @@ import java.math.BigDecimal;
 import java.net.InetSocketAddress;
 import java.net.Socket;
 import java.net.SocketAddress;
+import java.text.DecimalFormat;
 import java.util.*;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
@@ -30,7 +31,11 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 	private static final Logger LOGGER = LogManager.getLogger(ElectrumX.class);
 	private static final Random RANDOM = new Random();
 
+	// See: https://electrumx.readthedocs.io/en/latest/protocol-changes.html
 	private static final double MIN_PROTOCOL_VERSION = 1.2;
+	private static final double MAX_PROTOCOL_VERSION = 2.0; // Higher than current latest, for hopeful future-proofing
+	private static final String CLIENT_NAME = "Qortal";
+
 	private static final int BLOCK_HEADER_LENGTH = 80;
 
 	// "message": "daemon error: DaemonError({'code': -5, 'message': 'No such mempool or blockchain transaction. Use gettransaction for wallet transactions.'})"
@@ -40,7 +45,7 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 	private static final String VERBOSE_TRANSACTIONS_UNSUPPORTED_MESSAGE = "verbose transactions are currently unsupported";
 
 	private static final int RESPONSE_TIME_READINGS = 5;
-	private static final long MAX_AVG_RESPONSE_TIME = 500L; // ms
+	private static final long MAX_AVG_RESPONSE_TIME = 1000L; // ms
 
 	public static class Server {
 		String hostname;
@@ -679,6 +684,9 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 				this.scanner = new Scanner(this.socket.getInputStream());
 				this.scanner.useDelimiter("\n");
 
+				// All connections need to start with a version negotiation
+				this.connectedRpc("server.version");
+
 				// Check connection is suitable by asking for server features, including genesis block hash
 				JSONObject featuresJson = (JSONObject) this.connectedRpc("server.features");
 
@@ -725,6 +733,17 @@ public class ElectrumX extends BitcoinyBlockchainProvider {
 
 		JSONArray requestParams = new JSONArray();
 		requestParams.addAll(Arrays.asList(params));
+
+		// server.version needs additional params to negotiate a version
+		if (method.equals("server.version")) {
+			requestParams.add(CLIENT_NAME);
+			List<String> versions = new ArrayList<>();
+			DecimalFormat df = new DecimalFormat("#.#");
+			versions.add(df.format(MIN_PROTOCOL_VERSION));
+			versions.add(df.format(MAX_PROTOCOL_VERSION));
+			requestParams.add(versions);
+		}
+
 		requestJson.put("params", requestParams);
 
 		String request = requestJson.toJSONString() + "\n";

src/main/java/org/qortal/crosschain/Litecoin.java

@@ -45,15 +45,19 @@ public class Litecoin extends Bitcoiny {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
 						// Status verified at https://1209k.com/bitcoin-eye/ele.php?chain=ltc
-						//CLOSED new Server("electrum-ltc.petrkr.net", Server.ConnectionType.SSL, 60002),
 						//CLOSED new Server("electrum-ltc.someguy123.net", Server.ConnectionType.SSL, 50002),
+						//CLOSED new Server("ltc.litepay.ch", Server.ConnectionType.SSL, 50022),
+						//BEHIND new Server("62.171.169.176", Server.ConnectionType.SSL, 50002),
 						//PHISHY new Server("electrum-ltc.bysh.me", Server.ConnectionType.SSL, 50002),
 						new Server("backup.electrum-ltc.org", Server.ConnectionType.SSL, 443),
+						new Server("electrum.qortal.link", Server.ConnectionType.SSL, 50002),
 						new Server("electrum.ltc.xurious.com", Server.ConnectionType.SSL, 50002),
+						new Server("electrum-ltc.petrkr.net", Server.ConnectionType.SSL, 60002),
+						new Server("electrum-ltc.qortal.online", Server.ConnectionType.SSL, 50002),
+						new Server("electrum1-ltc.qortal.online", Server.ConnectionType.SSL, 50002),
 						new Server("electrum1.cipig.net", Server.ConnectionType.SSL, 20063),
 						new Server("electrum2.cipig.net", Server.ConnectionType.SSL, 20063),
 						new Server("electrum3.cipig.net", Server.ConnectionType.SSL, 20063),
-						new Server("ltc.litepay.ch", Server.ConnectionType.SSL, 50022),
 						new Server("ltc.rentonrisk.com", Server.ConnectionType.SSL, 50002));
 			}
 

src/main/java/org/qortal/crosschain/PirateChain.java

@@ -57,9 +57,9 @@ public class PirateChain extends Bitcoiny {
 			public Collection<Server> getServers() {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
-						new Server("arrrlightd.qortal.online", ConnectionType.SSL, 443),
-						new Server("arrrlightd1.qortal.online", ConnectionType.SSL, 443),
-						new Server("arrrlightd2.qortal.online", ConnectionType.SSL, 443),
+						new Server("wallet-arrr1.qortal.online", ConnectionType.SSL, 443),
+						new Server("wallet-arrr2.qortal.online", ConnectionType.SSL, 443),
+						new Server("wallet-arrr3.qortal.online", ConnectionType.SSL, 443),
 						new Server("lightd.pirate.black", ConnectionType.SSL, 443));
 			}
 

src/main/java/org/qortal/crosschain/PirateWallet.java

@@ -117,7 +117,7 @@ public class PirateWallet {
                 // Restore existing wallet
                 String response = LiteWalletJni.initfromb64(serverUri, params, wallet, saplingOutput64, saplingSpend64);
                 if (response != null && !response.contains("\"initalized\":true")) {
-                    LOGGER.info("Unable to initialize Pirate Chain wallet: {}", response);
+                    LOGGER.info("Unable to initialize Pirate Chain wallet at {}: {}", serverUri, response);
                     return false;
                 }
                 this.seedPhrase = inputSeedPhrase;

src/main/java/org/qortal/crosschain/Ravencoin.java

@@ -45,13 +45,17 @@ public class Ravencoin extends Bitcoiny {
 				return Arrays.asList(
 						// Servers chosen on NO BASIS WHATSOEVER from various sources!
 						// Status verified at https://1209k.com/bitcoin-eye/ele.php?chain=rvn
-						new Server("aethyn.com", ConnectionType.SSL, 50002),
-						new Server("electrum2.rvn.rocks", ConnectionType.SSL, 50002),
-						new Server("rvn-dashboard.com", ConnectionType.SSL, 50002),
-						new Server("rvn4lyfe.com", ConnectionType.SSL, 50002),
+						//CLOSED new Server("aethyn.com", ConnectionType.SSL, 50002),
+						//CLOSED new Server("electrum2.rvn.rocks", ConnectionType.SSL, 50002),
+						//BEHIND new Server("electrum3.rvn.rocks", ConnectionType.SSL, 50002),
+						new Server("electrum.qortal.link", Server.ConnectionType.SSL, 56002),
+						new Server("electrum-rvn.qortal.online", ConnectionType.SSL, 50002),
+						new Server("electrum1-rvn.qortal.online", ConnectionType.SSL, 50002),
 						new Server("electrum1.cipig.net", ConnectionType.SSL, 20051),
 						new Server("electrum2.cipig.net", ConnectionType.SSL, 20051),
-						new Server("electrum3.cipig.net", ConnectionType.SSL, 20051));
+						new Server("electrum3.cipig.net", ConnectionType.SSL, 20051),
+						new Server("rvn-dashboard.com", ConnectionType.SSL, 50002),
+						new Server("rvn4lyfe.com", ConnectionType.SSL, 50002));
 			}
 
 			@Override
@@ -138,6 +142,8 @@ public class Ravencoin extends Bitcoiny {
 			Context bitcoinjContext = new Context(ravencoinNet.getParams());
 
 			instance = new Ravencoin(ravencoinNet, electrumX, bitcoinjContext, CURRENCY_CODE);
+
+			electrumX.setBlockchain(instance);
 		}
 
 		return instance;

src/main/java/org/qortal/data/arbitrary/ArbitraryResourceMetadata.java

@@ -15,22 +15,24 @@ public class ArbitraryResourceMetadata {
     private List<String> tags;
     private Category category;
     private String categoryName;
+    private List<String> files;
 
     public ArbitraryResourceMetadata() {
     }
 
-    public ArbitraryResourceMetadata(String title, String description, List<String> tags, Category category) {
+    public ArbitraryResourceMetadata(String title, String description, List<String> tags, Category category, List<String> files) {
         this.title = title;
         this.description = description;
         this.tags = tags;
         this.category = category;
+        this.files = files;
 
         if (category != null) {
             this.categoryName = category.getName();
         }
     }
 
-    public static ArbitraryResourceMetadata fromTransactionMetadata(ArbitraryDataTransactionMetadata transactionMetadata) {
+    public static ArbitraryResourceMetadata fromTransactionMetadata(ArbitraryDataTransactionMetadata transactionMetadata, boolean includeFileList) {
         if (transactionMetadata == null) {
             return null;
         }
@@ -39,10 +41,20 @@ public class ArbitraryResourceMetadata {
         List<String> tags = transactionMetadata.getTags();
         Category category = transactionMetadata.getCategory();
 
-        if (title == null && description == null && tags == null && category == null) {
+        // We don't always want to include the file list as it can be too verbose
+        List<String> files = null;
+        if (includeFileList) {
+            files = transactionMetadata.getFiles();
+        }
+
+        if (title == null && description == null && tags == null && category == null && files == null) {
             return null;
         }
 
-        return new ArbitraryResourceMetadata(title, description, tags, category);
+        return new ArbitraryResourceMetadata(title, description, tags, category, files);
+    }
+
+    public List<String> getFiles() {
+        return this.files;
     }
 }

src/main/java/org/qortal/data/chat/ActiveChats.java

@@ -1,10 +1,15 @@
 package org.qortal.data.chat;
 
+import org.bouncycastle.util.encoders.Base64;
+import org.qortal.utils.Base58;
+
 import java.util.List;
 
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 @XmlAccessorType(XmlAccessType.FIELD)
 public class ActiveChats {
 
@@ -17,17 +22,39 @@ public class ActiveChats {
 		private Long timestamp;
 		private String sender;
 		private String senderName;
+		private byte[] signature;
+		private Encoding encoding;
+		private String data;
 
 		protected GroupChat() {
 			/* JAXB */
 		}
 
-		public GroupChat(int groupId, String groupName, Long timestamp, String sender, String senderName) {
+		public GroupChat(int groupId, String groupName, Long timestamp, String sender, String senderName,
+						 byte[] signature, Encoding encoding, byte[] data) {
 			this.groupId = groupId;
 			this.groupName = groupName;
 			this.timestamp = timestamp;
 			this.sender = sender;
 			this.senderName = senderName;
+			this.signature = signature;
+			this.encoding = encoding != null ? encoding : Encoding.BASE58;
+
+			if (data != null) {
+				switch (this.encoding) {
+					case BASE64:
+						this.data = Base64.toBase64String(data);
+						break;
+
+					case BASE58:
+					default:
+						this.data = Base58.encode(data);
+						break;
+				}
+			}
+			else {
+				this.data = null;
+			}
 		}
 
 		public int getGroupId() {
@@ -49,6 +76,14 @@ public class ActiveChats {
 		public String getSenderName() {
 			return this.senderName;
 		}
+
+		public byte[] getSignature() {
+			return this.signature;
+		}
+
+		public String getData() {
+			return this.data;
+		}
 	}
 
 	@XmlAccessorType(XmlAccessType.FIELD)
@@ -118,4 +153,4 @@ public class ActiveChats {
 		return this.direct;
 	}
 
-}
+}

src/main/java/org/qortal/data/chat/ChatMessage.java

@@ -1,11 +1,19 @@
 package org.qortal.data.chat;
 
+import org.bouncycastle.util.encoders.Base64;
+import org.qortal.utils.Base58;
+
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
 
 @XmlAccessorType(XmlAccessType.FIELD)
 public class ChatMessage {
 
+	public enum Encoding {
+		BASE58,
+		BASE64
+	}
+
 	// Properties
 
 	private long timestamp;
@@ -27,7 +35,11 @@ public class ChatMessage {
 
 	private String recipientName;
 
-	private byte[] data;
+	private byte[] chatReference;
+
+	private Encoding encoding;
+
+	private String data;
 
 	private boolean isText;
 	private boolean isEncrypted;
@@ -42,8 +54,8 @@ public class ChatMessage {
 
 	// For repository use
 	public ChatMessage(long timestamp, int txGroupId, byte[] reference, byte[] senderPublicKey, String sender,
-			String senderName, String recipient, String recipientName, byte[] data, boolean isText,
-			boolean isEncrypted, byte[] signature) {
+					   String senderName, String recipient, String recipientName, byte[] chatReference,
+					   Encoding encoding, byte[] data, boolean isText, boolean isEncrypted, byte[] signature) {
 		this.timestamp = timestamp;
 		this.txGroupId = txGroupId;
 		this.reference = reference;
@@ -52,7 +64,25 @@ public class ChatMessage {
 		this.senderName = senderName;
 		this.recipient = recipient;
 		this.recipientName = recipientName;
-		this.data = data;
+		this.chatReference = chatReference;
+		this.encoding = encoding != null ? encoding : Encoding.BASE58;
+
+		if (data != null) {
+			switch (this.encoding) {
+				case BASE64:
+					this.data = Base64.toBase64String(data);
+					break;
+
+				case BASE58:
+				default:
+					this.data = Base58.encode(data);
+					break;
+			}
+		}
+		else {
+			this.data = null;
+		}
+
 		this.isText = isText;
 		this.isEncrypted = isEncrypted;
 		this.signature = signature;
@@ -90,7 +120,11 @@ public class ChatMessage {
 		return this.recipientName;
 	}
 
-	public byte[] getData() {
+	public byte[] getChatReference() {
+		return this.chatReference;
+	}
+
+	public String getData() {
 		return this.data;
 	}
 

src/main/java/org/qortal/data/transaction/ArbitraryTransactionData.java

@@ -73,7 +73,7 @@ public class ArbitraryTransactionData extends TransactionData {
 	@Schema(example = "sender_public_key")
 	private byte[] senderPublicKey;
 
-	private Service service;
+	private int service;
 	private int nonce;
 	private int size;
 
@@ -103,7 +103,7 @@ public class ArbitraryTransactionData extends TransactionData {
 	}
 
 	public ArbitraryTransactionData(BaseTransactionData baseTransactionData,
-									int version, Service service, int nonce, int size,
+									int version, int service, int nonce, int size,
 									String name, String identifier, Method method, byte[] secret, Compression compression,
 									byte[] data, DataType dataType, byte[] metadataHash, List<PaymentData> payments) {
 		super(TransactionType.ARBITRARY, baseTransactionData);
@@ -135,6 +135,10 @@ public class ArbitraryTransactionData extends TransactionData {
 	}
 
 	public Service getService() {
+		return Service.valueOf(this.service);
+	}
+
+	public int getServiceInt() {
 		return this.service;
 	}
 

src/main/java/org/qortal/data/transaction/CancelSellNameTransactionData.java

@@ -3,6 +3,7 @@ package org.qortal.data.transaction;
 import javax.xml.bind.Unmarshaller;
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlTransient;
 
 import org.qortal.transaction.Transaction.TransactionType;
 
@@ -19,6 +20,11 @@ public class CancelSellNameTransactionData extends TransactionData {
 	@Schema(description = "which name to cancel selling", example = "my-name")
 	private String name;
 
+	// For internal use when orphaning
+	@XmlTransient
+	@Schema(hidden = true)
+	private Long salePrice;
+
 	// Constructors
 
 	// For JAXB
@@ -30,11 +36,17 @@ public class CancelSellNameTransactionData extends TransactionData {
 		this.creatorPublicKey = this.ownerPublicKey;
 	}
 
-	public CancelSellNameTransactionData(BaseTransactionData baseTransactionData, String name) {
+	public CancelSellNameTransactionData(BaseTransactionData baseTransactionData, String name, Long salePrice) {
 		super(TransactionType.CANCEL_SELL_NAME, baseTransactionData);
 
 		this.ownerPublicKey = baseTransactionData.creatorPublicKey;
 		this.name = name;
+		this.salePrice = salePrice;
+	}
+
+	/** From network/API */
+	public CancelSellNameTransactionData(BaseTransactionData baseTransactionData, String name) {
+		this(baseTransactionData, name, null);
 	}
 
 	// Getters / setters
@@ -47,4 +59,12 @@ public class CancelSellNameTransactionData extends TransactionData {
 		return this.name;
 	}
 
+	public Long getSalePrice() {
+		return this.salePrice;
+	}
+
+	public void setSalePrice(Long salePrice) {
+		this.salePrice = salePrice;
+	}
+
 }

src/main/java/org/qortal/data/transaction/ChatTransactionData.java

@@ -26,6 +26,8 @@ public class ChatTransactionData extends TransactionData {
 
 	private String recipient; // can be null
 
+	private byte[] chatReference; // can be null
+
 	@Schema(description = "raw message data, possibly UTF8 text", example = "2yGEbwRFyhPZZckKA")
 	private byte[] data;
 
@@ -44,13 +46,14 @@ public class ChatTransactionData extends TransactionData {
 	}
 
 	public ChatTransactionData(BaseTransactionData baseTransactionData,
-			String sender, int nonce, String recipient, byte[] data, boolean isText, boolean isEncrypted) {
+			String sender, int nonce, String recipient, byte[] chatReference, byte[] data, boolean isText, boolean isEncrypted) {
 		super(TransactionType.CHAT, baseTransactionData);
 
 		this.senderPublicKey = baseTransactionData.creatorPublicKey;
 		this.sender = sender;
 		this.nonce = nonce;
 		this.recipient = recipient;
+		this.chatReference = chatReference;
 		this.data = data;
 		this.isText = isText;
 		this.isEncrypted = isEncrypted;
@@ -78,6 +81,14 @@ public class ChatTransactionData extends TransactionData {
 		return this.recipient;
 	}
 
+	public byte[] getChatReference() {
+		return this.chatReference;
+	}
+
+	public void setChatReference(byte[] chatReference) {
+		this.chatReference = chatReference;
+	}
+
 	public byte[] getData() {
 		return this.data;
 	}

src/main/java/org/qortal/data/transaction/DeployAtTransactionData.java

@@ -2,6 +2,7 @@ package org.qortal.data.transaction;
 
 import javax.xml.bind.annotation.XmlAccessType;
 import javax.xml.bind.annotation.XmlAccessorType;
+import javax.xml.bind.annotation.XmlElement;
 import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
 
 import org.qortal.transaction.Transaction.TransactionType;
@@ -90,4 +91,17 @@ public class DeployAtTransactionData extends TransactionData {
 		this.aTAddress = AtAddress;
 	}
 
+	// Re-expose creatorPublicKey for this transaction type for JAXB
+	@XmlElement(name = "creatorPublicKey")
+	@Schema(name = "creatorPublicKey", description = "AT creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	public byte[] getAtCreatorPublicKey() {
+		return this.creatorPublicKey;
+	}
+
+	@XmlElement(name = "creatorPublicKey")
+	@Schema(name = "creatorPublicKey", description = "AT creator's public key", example = "2tiMr5LTpaWCgbRvkPK8TFd7k63DyHJMMFFsz9uBf1ZP")
+	public void setAtCreatorPublicKey(byte[] creatorPublicKey) {
+		this.creatorPublicKey = creatorPublicKey;
+	}
+
 }

src/main/java/org/qortal/naming/Name.java

@@ -16,6 +16,8 @@ import org.qortal.repository.Repository;
 import org.qortal.transaction.Transaction.TransactionType;
 import org.qortal.utils.Unicode;
 
+import java.util.Objects;
+
 public class Name {
 
 	// Properties
@@ -116,7 +118,7 @@ public class Name {
 
 		this.repository.getNameRepository().save(this.nameData);
 
-		if (!updateNameTransactionData.getNewName().isEmpty())
+		if (!updateNameTransactionData.getNewName().isEmpty() && !Objects.equals(updateNameTransactionData.getName(), updateNameTransactionData.getNewName()))
 			// Name has changed, delete old entry
 			this.repository.getNameRepository().delete(updateNameTransactionData.getNewName());
 
@@ -180,8 +182,12 @@ public class Name {
 	}
 
 	public void cancelSell(CancelSellNameTransactionData cancelSellNameTransactionData) throws DataException {
-		// Mark not for-sale but leave price in case we want to orphan
+		// Update previous sale price in transaction data
+		cancelSellNameTransactionData.setSalePrice(this.nameData.getSalePrice());
+
+		// Mark not for-sale
 		this.nameData.setIsForSale(false);
+		this.nameData.setSalePrice(null);
 
 		// Save sale info into repository
 		this.repository.getNameRepository().save(this.nameData);
@@ -190,6 +196,7 @@ public class Name {
 	public void uncancelSell(CancelSellNameTransactionData cancelSellNameTransactionData) throws DataException {
 		// Mark as for-sale using existing price
 		this.nameData.setIsForSale(true);
+		this.nameData.setSalePrice(cancelSellNameTransactionData.getSalePrice());
 
 		// Save no-sale info into repository
 		this.repository.getNameRepository().save(this.nameData);

src/main/java/org/qortal/network/Handshake.java

@@ -265,7 +265,7 @@ public enum Handshake {
 	private static final long PEER_VERSION_131 = 0x0100030001L;
 
 	/** Minimum peer version that we are allowed to communicate with */
-	private static final String MIN_PEER_VERSION = "3.7.0";
+	private static final String MIN_PEER_VERSION = "3.8.2";
 
 	private static final int POW_BUFFER_SIZE_PRE_131 = 8 * 1024 * 1024; // bytes
 	private static final int POW_DIFFICULTY_PRE_131 = 8; // leading zero bits

src/main/java/org/qortal/network/Network.java

@@ -339,7 +339,7 @@ public class Network {
                 try {
                     if (!isConnected) {
                         // Add this signature to the list of pending requests for this peer
-                        LOGGER.info("Making connection to peer {} to request files for signature {}...", peerAddressString, Base58.encode(signature));
+                        LOGGER.debug("Making connection to peer {} to request files for signature {}...", peerAddressString, Base58.encode(signature));
                         Peer peer = new Peer(peerData);
                         peer.setIsDataPeer(true);
                         peer.addPendingSignatureRequest(signature);

src/main/java/org/qortal/network/Peer.java

@@ -155,6 +155,11 @@ public class Peer {
      */
     private CommonBlockData commonBlockData;
 
+    /**
+     * Last time we detected this peer as TOO_DIVERGENT
+     */
+    private Long lastTooDivergentTime;
+
     // Message stats
 
     private static class MessageStats {
@@ -383,6 +388,14 @@ public class Peer {
         this.commonBlockData = commonBlockData;
     }
 
+    public Long getLastTooDivergentTime() {
+        return this.lastTooDivergentTime;
+    }
+
+    public void setLastTooDivergentTime(Long lastTooDivergentTime) {
+        this.lastTooDivergentTime = lastTooDivergentTime;
+    }
+
     public boolean isSyncInProgress() {
         return this.syncInProgress;
     }

src/main/java/org/qortal/network/message/CachedBlockV2Message.java

@@ -0,0 +1,43 @@
+package org.qortal.network.message;
+
+import com.google.common.primitives.Ints;
+import org.qortal.block.Block;
+import org.qortal.transform.TransformationException;
+import org.qortal.transform.block.BlockTransformer;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+// This is an OUTGOING-only Message which more readily lends itself to being cached
+public class CachedBlockV2Message extends Message implements Cloneable {
+
+	public CachedBlockV2Message(Block block) throws TransformationException {
+		super(MessageType.BLOCK_V2);
+
+		ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+		try {
+			bytes.write(Ints.toByteArray(block.getBlockData().getHeight()));
+
+			bytes.write(BlockTransformer.toBytes(block));
+		} catch (IOException e) {
+			throw new AssertionError("IOException shouldn't occur with ByteArrayOutputStream");
+		}
+
+		this.dataBytes = bytes.toByteArray();
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	public CachedBlockV2Message(byte[] cachedBytes) {
+		super(MessageType.BLOCK_V2);
+
+		this.dataBytes = cachedBytes;
+		this.checksumBytes = Message.generateChecksum(this.dataBytes);
+	}
+
+	public static Message fromByteBuffer(int id, ByteBuffer byteBuffer) {
+		throw new UnsupportedOperationException("CachedBlockMessageV2 is for outgoing messages only");
+	}
+
+}

src/main/java/org/qortal/repository/ATRepository.java

@@ -119,7 +119,7 @@ public interface ATRepository {
 	 * <p>
 	 * NOTE: performs implicit <tt>repository.saveChanges()</tt>.
 	 */
-	public void rebuildLatestAtStates() throws DataException;
+	public void rebuildLatestAtStates(int maxHeight) throws DataException;
 
 
 	/** Returns height of first trimmable AT state. */

src/main/java/org/qortal/repository/BlockArchiveReader.java

@@ -3,10 +3,7 @@ package org.qortal.repository;
 import com.google.common.primitives.Ints;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
-import org.qortal.data.at.ATStateData;
 import org.qortal.data.block.BlockArchiveData;
-import org.qortal.data.block.BlockData;
-import org.qortal.data.transaction.TransactionData;
 import org.qortal.settings.Settings;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.block.BlockTransformation;
@@ -67,20 +64,51 @@ public class BlockArchiveReader {
         this.fileListCache = Map.copyOf(map);
     }
 
+    public Integer fetchSerializationVersionForHeight(int height) {
+        if (this.fileListCache == null) {
+            this.fetchFileList();
+        }
+
+        Triple<byte[], Integer, Integer> serializedBlock = this.fetchSerializedBlockBytesForHeight(height);
+        if (serializedBlock == null) {
+            return null;
+        }
+        Integer serializationVersion = serializedBlock.getB();
+        return serializationVersion;
+    }
+
     public BlockTransformation fetchBlockAtHeight(int height) {
         if (this.fileListCache == null) {
             this.fetchFileList();
         }
 
-        byte[] serializedBytes = this.fetchSerializedBlockBytesForHeight(height);
-        if (serializedBytes == null) {
+        Triple<byte[], Integer, Integer> serializedBlock = this.fetchSerializedBlockBytesForHeight(height);
+        if (serializedBlock == null) {
+            return null;
+        }
+        byte[] serializedBytes = serializedBlock.getA();
+        Integer serializationVersion = serializedBlock.getB();
+        if (serializedBytes == null || serializationVersion == null) {
             return null;
         }
 
         ByteBuffer byteBuffer = ByteBuffer.wrap(serializedBytes);
         BlockTransformation blockInfo = null;
         try {
-            blockInfo = BlockTransformer.fromByteBuffer(byteBuffer);
+            switch (serializationVersion) {
+                case 1:
+                    blockInfo = BlockTransformer.fromByteBuffer(byteBuffer);
+                    break;
+
+                case 2:
+                    blockInfo = BlockTransformer.fromByteBufferV2(byteBuffer);
+                    break;
+
+                default:
+                    // Invalid serialization version
+                    return null;
+            }
+
             if (blockInfo != null && blockInfo.getBlockData() != null) {
                 // Block height is stored outside of the main serialized bytes, so it
                 // won't be set automatically.
@@ -168,15 +196,20 @@ public class BlockArchiveReader {
         return null;
     }
 
-    public byte[] fetchSerializedBlockBytesForSignature(byte[] signature, boolean includeHeightPrefix, Repository repository) {
+    public Triple<byte[], Integer, Integer> fetchSerializedBlockBytesForSignature(byte[] signature, boolean includeHeightPrefix, Repository repository) {
         if (this.fileListCache == null) {
             this.fetchFileList();
         }
 
         Integer height = this.fetchHeightForSignature(signature, repository);
         if (height != null) {
-            byte[] blockBytes = this.fetchSerializedBlockBytesForHeight(height);
-            if (blockBytes == null) {
+            Triple<byte[], Integer, Integer> serializedBlock = this.fetchSerializedBlockBytesForHeight(height);
+            if (serializedBlock == null) {
+                return null;
+            }
+            byte[] blockBytes = serializedBlock.getA();
+            Integer version = serializedBlock.getB();
+            if (blockBytes == null || version == null) {
                 return null;
             }
 
@@ -187,18 +220,18 @@ public class BlockArchiveReader {
                 try {
                     bytes.write(Ints.toByteArray(height));
                     bytes.write(blockBytes);
-                    return bytes.toByteArray();
+                    return new Triple<>(bytes.toByteArray(), version, height);
 
                 } catch (IOException e) {
                     return null;
                 }
             }
-            return blockBytes;
+            return new Triple<>(blockBytes, version, height);
         }
         return null;
     }
 
-    public byte[] fetchSerializedBlockBytesForHeight(int height) {
+    public Triple<byte[], Integer, Integer> fetchSerializedBlockBytesForHeight(int height) {
         String filename = this.getFilenameForHeight(height);
         if (filename == null) {
             // We don't have this block in the archive
@@ -221,7 +254,7 @@ public class BlockArchiveReader {
             // End of fixed length header
 
             // Make sure the version is one we recognize
-            if (version != 1) {
+            if (version != 1 && version != 2) {
                 LOGGER.info("Error: unknown version in file {}: {}", filename, version);
                 return null;
             }
@@ -258,7 +291,7 @@ public class BlockArchiveReader {
             byte[] blockBytes = new byte[blockLength];
             file.read(blockBytes);
 
-            return blockBytes;
+            return new Triple<>(blockBytes, version, height);
 
         } catch (FileNotFoundException e) {
             LOGGER.info("File {} not found: {}", filename, e.getMessage());
@@ -279,6 +312,30 @@ public class BlockArchiveReader {
         }
     }
 
+    public int getHeightOfLastArchivedBlock() {
+        if (this.fileListCache == null) {
+            this.fetchFileList();
+        }
+
+        int maxEndHeight = 0;
+
+        Iterator it = this.fileListCache.entrySet().iterator();
+        while (it.hasNext()) {
+            Map.Entry pair = (Map.Entry) it.next();
+            if (pair == null && pair.getKey() == null && pair.getValue() == null) {
+                continue;
+            }
+            Triple<Integer, Integer, Integer> heightInfo = (Triple<Integer, Integer, Integer>) pair.getValue();
+            Integer endHeight = heightInfo.getB();
+
+            if (endHeight != null && endHeight > maxEndHeight) {
+                maxEndHeight = endHeight;
+            }
+        }
+
+        return maxEndHeight;
+    }
+
     public void invalidateFileListCache() {
         this.fileListCache = null;
     }

src/main/java/org/qortal/repository/BlockArchiveWriter.java

@@ -6,10 +6,13 @@ import org.apache.logging.log4j.Logger;
 import org.qortal.block.Block;
 import org.qortal.controller.Controller;
 import org.qortal.controller.Synchronizer;
+import org.qortal.data.at.ATStateData;
 import org.qortal.data.block.BlockArchiveData;
 import org.qortal.data.block.BlockData;
+import org.qortal.data.transaction.TransactionData;
 import org.qortal.settings.Settings;
 import org.qortal.transform.TransformationException;
+import org.qortal.transform.block.BlockTransformation;
 import org.qortal.transform.block.BlockTransformer;
 
 import java.io.ByteArrayOutputStream;
@@ -18,6 +21,7 @@ import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.List;
 
 public class BlockArchiveWriter {
 
@@ -28,25 +32,78 @@ public class BlockArchiveWriter {
         BLOCK_NOT_FOUND
     }
 
+    public enum BlockArchiveDataSource {
+        BLOCK_REPOSITORY, // To build an archive from the Blocks table
+        BLOCK_ARCHIVE // To build a new archive from an existing archive
+    }
+
     private static final Logger LOGGER = LogManager.getLogger(BlockArchiveWriter.class);
 
-    public static final long DEFAULT_FILE_SIZE_TARGET = 100 * 1024 * 1024; // 100MiB
+    public static final long DEFAULT_FILE_SIZE_TARGET_V1 = 100 * 1024 * 1024; // 100MiB
+    public static final long DEFAULT_FILE_SIZE_TARGET_V2 = 10 * 1024 * 1024; // 10MiB
 
     private int startHeight;
     private final int endHeight;
+    private final Integer serializationVersion;
+    private final Path archivePath;
     private final Repository repository;
 
-    private long fileSizeTarget = DEFAULT_FILE_SIZE_TARGET;
+    private long fileSizeTarget = DEFAULT_FILE_SIZE_TARGET_V1;
     private boolean shouldEnforceFileSizeTarget = true;
 
+    // Default data source to BLOCK_REPOSITORY; can optionally be overridden
+    private BlockArchiveDataSource dataSource = BlockArchiveDataSource.BLOCK_REPOSITORY;
+
+    private boolean shouldLogProgress = false;
+
     private int writtenCount;
     private int lastWrittenHeight;
     private Path outputPath;
 
-    public BlockArchiveWriter(int startHeight, int endHeight, Repository repository) {
+    /**
+     * Instantiate a BlockArchiveWriter using a custom archive path
+     * @param startHeight
+     * @param endHeight
+     * @param repository
+     */
+    public BlockArchiveWriter(int startHeight, int endHeight, Integer serializationVersion, Path archivePath, Repository repository) {
         this.startHeight = startHeight;
         this.endHeight = endHeight;
+        this.archivePath = archivePath.toAbsolutePath();
         this.repository = repository;
+
+        if (serializationVersion == null) {
+            // When serialization version isn't specified, fetch it from the existing archive
+            serializationVersion = this.findSerializationVersion();
+        }
+
+        // Reduce default file size target if we're using V2, as the average block size is over 90% smaller
+        if (serializationVersion == 2) {
+            this.setFileSizeTarget(DEFAULT_FILE_SIZE_TARGET_V2);
+        }
+
+        this.serializationVersion = serializationVersion;
+    }
+
+    /**
+     * Instantiate a BlockArchiveWriter using the default archive path and version
+     * @param startHeight
+     * @param endHeight
+     * @param repository
+     */
+    public BlockArchiveWriter(int startHeight, int endHeight, Repository repository) {
+        this(startHeight, endHeight, null, Paths.get(Settings.getInstance().getRepositoryPath(), "archive"), repository);
+    }
+
+    private int findSerializationVersion() {
+        // Attempt to fetch the serialization version from the existing archive
+        Integer block2SerializationVersion = BlockArchiveReader.getInstance().fetchSerializationVersionForHeight(2);
+        if (block2SerializationVersion != null) {
+            return block2SerializationVersion;
+        }
+
+        // Default to version specified in settings
+        return Settings.getInstance().getDefaultArchiveVersion();
     }
 
     public static int getMaxArchiveHeight(Repository repository) throws DataException {
@@ -72,8 +129,7 @@ public class BlockArchiveWriter {
 
     public BlockArchiveWriteResult write() throws DataException, IOException, TransformationException, InterruptedException {
         // Create the archive folder if it doesn't exist
-        // This is a subfolder of the db directory, to make bootstrapping easier
-        Path archivePath = Paths.get(Settings.getInstance().getRepositoryPath(), "archive").toAbsolutePath();
+        // This is generally a subfolder of the db directory, to make bootstrapping easier
         try {
             Files.createDirectories(archivePath);
         } catch (IOException e) {
@@ -95,13 +151,13 @@ public class BlockArchiveWriter {
 
         LOGGER.info(String.format("Fetching blocks from height %d...", startHeight));
         int i = 0;
-        while (headerBytes.size() + bytes.size() < this.fileSizeTarget
-                || this.shouldEnforceFileSizeTarget == false) {
+        while (headerBytes.size() + bytes.size() < this.fileSizeTarget) {
 
             if (Controller.isStopping()) {
                 return BlockArchiveWriteResult.STOPPING;
             }
             if (Synchronizer.getInstance().isSynchronizing()) {
+                Thread.sleep(1000L);
                 continue;
             }
 
@@ -112,7 +168,28 @@ public class BlockArchiveWriter {
 
             //LOGGER.info("Fetching block {}...", currentHeight);
 
-            BlockData blockData = repository.getBlockRepository().fromHeight(currentHeight);
+            BlockData blockData = null;
+            List<TransactionData> transactions = null;
+            List<ATStateData> atStates = null;
+            byte[] atStatesHash = null;
+
+            switch (this.dataSource) {
+                case BLOCK_ARCHIVE:
+                    BlockTransformation archivedBlock = BlockArchiveReader.getInstance().fetchBlockAtHeight(currentHeight);
+                    if (archivedBlock != null) {
+                        blockData = archivedBlock.getBlockData();
+                        transactions = archivedBlock.getTransactions();
+                        atStates = archivedBlock.getAtStates();
+                        atStatesHash = archivedBlock.getAtStatesHash();
+                    }
+                    break;
+
+                case BLOCK_REPOSITORY:
+                default:
+                    blockData = repository.getBlockRepository().fromHeight(currentHeight);
+                    break;
+            }
+
             if (blockData == null) {
                 return BlockArchiveWriteResult.BLOCK_NOT_FOUND;
             }
@@ -122,18 +199,50 @@ public class BlockArchiveWriter {
             repository.getBlockArchiveRepository().save(blockArchiveData);
             repository.saveChanges();
 
+            // Build the block
+            Block block;
+            if (atStatesHash != null) {
+                block = new Block(repository, blockData, transactions, atStatesHash);
+            }
+            else if (atStates != null) {
+                block = new Block(repository, blockData, transactions, atStates);
+            }
+            else {
+                block = new Block(repository, blockData);
+            }
+
             // Write the block data to some byte buffers
-            Block block = new Block(repository, blockData);
             int blockIndex = bytes.size();
             // Write block index to header
             headerBytes.write(Ints.toByteArray(blockIndex));
             // Write block height
             bytes.write(Ints.toByteArray(block.getBlockData().getHeight()));
-            byte[] blockBytes = BlockTransformer.toBytes(block);
+
+            // Get serialized block bytes
+            byte[] blockBytes;
+            switch (serializationVersion) {
+                case 1:
+                    blockBytes = BlockTransformer.toBytes(block);
+                    break;
+
+                case 2:
+                    blockBytes = BlockTransformer.toBytesV2(block);
+                    break;
+
+                default:
+                    throw new DataException("Invalid serialization version");
+            }
+
             // Write block length
             bytes.write(Ints.toByteArray(blockBytes.length));
             // Write block bytes
             bytes.write(blockBytes);
+
+            // Log every 1000 blocks
+            if (this.shouldLogProgress && i % 1000 == 0) {
+                LOGGER.info("Archived up to block height {}. Size of current file: {} bytes", currentHeight, (headerBytes.size() + bytes.size()));
+            }
+
             i++;
 
         }
@@ -147,11 +256,10 @@ public class BlockArchiveWriter {
 
         // We have enough blocks to create a new file
         int endHeight = startHeight + i - 1;
-        int version = 1;
         String filePath = String.format("%s/%d-%d.dat", archivePath.toString(), startHeight, endHeight);
         FileOutputStream fileOutputStream = new FileOutputStream(filePath);
         // Write version number
-        fileOutputStream.write(Ints.toByteArray(version));
+        fileOutputStream.write(Ints.toByteArray(serializationVersion));
         // Write start height
         fileOutputStream.write(Ints.toByteArray(startHeight));
         // Write end height
@@ -199,4 +307,12 @@ public class BlockArchiveWriter {
         this.shouldEnforceFileSizeTarget = shouldEnforceFileSizeTarget;
     }
 
+    public void setDataSource(BlockArchiveDataSource dataSource) {
+        this.dataSource = dataSource;
+    }
+
+    public void setShouldLogProgress(boolean shouldLogProgress) {
+        this.shouldLogProgress = shouldLogProgress;
+    }
+
 }

src/main/java/org/qortal/repository/Bootstrap.java

@@ -279,7 +279,9 @@ public class Bootstrap {
 
             LOGGER.info("Generating checksum file...");
             String checksum = Crypto.digestHexString(compressedOutputPath.toFile(), 1024*1024);
+            LOGGER.info("checksum: {}", checksum);
             Path checksumPath = Paths.get(String.format("%s.sha256", compressedOutputPath.toString()));
+            LOGGER.info("Writing checksum to path: {}", checksumPath);
             Files.writeString(checksumPath, checksum, StandardOpenOption.CREATE);
 
             // Return the path to the compressed bootstrap file

src/main/java/org/qortal/repository/ChatRepository.java

@@ -6,6 +6,8 @@ import org.qortal.data.chat.ActiveChats;
 import org.qortal.data.chat.ChatMessage;
 import org.qortal.data.transaction.ChatTransactionData;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 public interface ChatRepository {
 
 	/**
@@ -14,11 +16,12 @@ public interface ChatRepository {
 	 * Expects EITHER non-null txGroupID OR non-null sender and recipient addresses.
 	 */
 	public List<ChatMessage> getMessagesMatchingCriteria(Long before, Long after,
-			Integer txGroupId, byte[] reference, List<String> involving,
+			Integer txGroupId, byte[] reference, byte[] chatReferenceBytes, Boolean hasChatReference,
+			List<String> involving, String senderAddress, Encoding encoding,
 			Integer limit, Integer offset, Boolean reverse) throws DataException;
 
-	public ChatMessage toChatMessage(ChatTransactionData chatTransactionData) throws DataException;
+	public ChatMessage toChatMessage(ChatTransactionData chatTransactionData, Encoding encoding) throws DataException;
 
-	public ActiveChats getActiveChats(String address) throws DataException;
+	public ActiveChats getActiveChats(String address, Encoding encoding) throws DataException;
 
 }

src/main/java/org/qortal/repository/GroupRepository.java

@@ -131,7 +131,14 @@ public interface GroupRepository {
 
 	public GroupBanData getBan(int groupId, String member) throws DataException;
 
-	public boolean banExists(int groupId, String offender) throws DataException;
+	/**
+	 * IMPORTANT: when using banExists() as part of validation, the timestamp must be that of the transaction that
+	 * is calling banExists() as part of its validation. It must NOT be the current time, unless this is being
+	 * called outside of validation, as part of an on demand check for a ban existing (such as via an API call).
+	 * This is because we need to evaluate a ban's status based on the time of the subsequent transaction, as
+	 * validation will not occur at a fixed time for every node. For some, it could be months into the future.
+	 */
+	public boolean banExists(int groupId, String offender, long timestamp) throws DataException;
 
 	public List<GroupBanData> getGroupBans(int groupId, Integer limit, Integer offset, Boolean reverse) throws DataException;
 

src/main/java/org/qortal/repository/RepositoryManager.java

@@ -2,11 +2,6 @@ package org.qortal.repository;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
-import org.qortal.gui.SplashFrame;
-import org.qortal.repository.hsqldb.HSQLDBDatabaseArchiving;
-import org.qortal.repository.hsqldb.HSQLDBDatabasePruning;
-import org.qortal.repository.hsqldb.HSQLDBRepository;
-import org.qortal.settings.Settings;
 
 import java.sql.SQLException;
 import java.util.concurrent.TimeoutException;
@@ -61,62 +56,6 @@ public abstract class RepositoryManager {
 		}
 	}
 
-	public static boolean archive(Repository repository) {
-		if (Settings.getInstance().isLite()) {
-			// Lite nodes have no blockchain
-			return false;
-		}
-
-		// Bulk archive the database the first time we use archive mode
-		if (Settings.getInstance().isArchiveEnabled()) {
-			if (RepositoryManager.canArchiveOrPrune()) {
-				try {
-					return HSQLDBDatabaseArchiving.buildBlockArchive(repository, BlockArchiveWriter.DEFAULT_FILE_SIZE_TARGET);
-
-				} catch (DataException e) {
-					LOGGER.info("Unable to build block archive. The database may have been left in an inconsistent state.");
-				}
-			}
-			else {
-				LOGGER.info("Unable to build block archive due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
-				LOGGER.info("To bootstrap, stop the core and delete the db folder, then start the core again.");
-				SplashFrame.getInstance().updateStatus("Missing index. Bootstrapping is recommended.");
-			}
-		}
-		return false;
-	}
-
-	public static boolean prune(Repository repository) {
-		if (Settings.getInstance().isLite()) {
-			// Lite nodes have no blockchain
-			return false;
-		}
-
-		// Bulk prune the database the first time we use top-only or block archive mode
-		if (Settings.getInstance().isTopOnly() ||
-			Settings.getInstance().isArchiveEnabled()) {
-			if (RepositoryManager.canArchiveOrPrune()) {
-				try {
-					boolean prunedATStates = HSQLDBDatabasePruning.pruneATStates((HSQLDBRepository) repository);
-					boolean prunedBlocks = HSQLDBDatabasePruning.pruneBlocks((HSQLDBRepository) repository);
-
-					// Perform repository maintenance to shrink the db size down
-					if (prunedATStates && prunedBlocks) {
-						HSQLDBDatabasePruning.performMaintenance(repository);
-						return true;
-					}
-
-				} catch (SQLException | DataException e) {
-					LOGGER.info("Unable to bulk prune AT states. The database may have been left in an inconsistent state.");
-				}
-			}
-			else {
-				LOGGER.info("Unable to prune blocks due to missing ATStatesHeightIndex. Bootstrapping is recommended.");
-			}
-		}
-		return false;
-	}
-
 	public static void setRequestedCheckpoint(Boolean quick) {
 		quickCheckpointRequested = quick;
 	}

src/main/java/org/qortal/repository/hsqldb/HSQLDBATRepository.java

@@ -603,7 +603,7 @@ public class HSQLDBATRepository implements ATRepository {
 
 
 	@Override
-	public void rebuildLatestAtStates() throws DataException {
+	public void rebuildLatestAtStates(int maxHeight) throws DataException {
 		// latestATStatesLock is to prevent concurrent updates on LatestATStates
 		// that could result in one process using a partial or empty dataset
 		// because it was in the process of being rebuilt by another thread
@@ -624,11 +624,12 @@ public class HSQLDBATRepository implements ATRepository {
 					+ "CROSS JOIN LATERAL("
 					+ "SELECT height FROM ATStates "
 					+ "WHERE ATStates.AT_address = ATs.AT_address "
+					+ "AND height <= ?"
 					+ "ORDER BY AT_address DESC, height DESC LIMIT 1"
 					+ ") "
 					+ ")";
 			try {
-				this.repository.executeCheckedUpdate(insertSql);
+				this.repository.executeCheckedUpdate(insertSql, maxHeight);
 			} catch (SQLException e) {
 				repository.examineException(e);
 				throw new DataException("Unable to populate temporary latest AT states cache in repository", e);

src/main/java/org/qortal/repository/hsqldb/HSQLDBArbitraryRepository.java

@@ -202,7 +202,7 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 
 				int version = resultSet.getInt(11);
 				int nonce = resultSet.getInt(12);
-				Service serviceResult = Service.valueOf(resultSet.getInt(13));
+				int serviceInt = resultSet.getInt(13);
 				int size = resultSet.getInt(14);
 				boolean isDataRaw = resultSet.getBoolean(15); // NOT NULL, so no null to false
 				DataType dataType = isDataRaw ? DataType.RAW_DATA : DataType.DATA_HASH;
@@ -216,7 +216,7 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 				// FUTURE: get payments from signature if needed. Avoiding for now to reduce database calls.
 
 				ArbitraryTransactionData transactionData = new ArbitraryTransactionData(baseTransactionData,
-						version, serviceResult, nonce, size, nameResult, identifierResult, method, secret,
+						version, serviceInt, nonce, size, nameResult, identifierResult, method, secret,
 						compression, data, dataType, metadataHash, null);
 
 				arbitraryTransactionData.add(transactionData);
@@ -277,7 +277,7 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 
 			int version = resultSet.getInt(11);
 			int nonce = resultSet.getInt(12);
-			Service serviceResult = Service.valueOf(resultSet.getInt(13));
+			int serviceInt = resultSet.getInt(13);
 			int size = resultSet.getInt(14);
 			boolean isDataRaw = resultSet.getBoolean(15); // NOT NULL, so no null to false
 			DataType dataType = isDataRaw ? DataType.RAW_DATA : DataType.DATA_HASH;
@@ -291,7 +291,7 @@ public class HSQLDBArbitraryRepository implements ArbitraryRepository {
 			// FUTURE: get payments from signature if needed. Avoiding for now to reduce database calls.
 
 			ArbitraryTransactionData transactionData = new ArbitraryTransactionData(baseTransactionData,
-					version, serviceResult, nonce, size, nameResult, identifierResult, methodResult, secret,
+					version, serviceInt, nonce, size, nameResult, identifierResult, methodResult, secret,
 					compression, data, dataType, metadataHash, null);
 
 			return transactionData;

src/main/java/org/qortal/repository/hsqldb/HSQLDBChatRepository.java

@@ -14,6 +14,8 @@ import org.qortal.repository.ChatRepository;
 import org.qortal.repository.DataException;
 import org.qortal.transaction.Transaction.TransactionType;
 
+import static org.qortal.data.chat.ChatMessage.Encoding;
+
 public class HSQLDBChatRepository implements ChatRepository {
 
 	protected HSQLDBRepository repository;
@@ -24,8 +26,8 @@ public class HSQLDBChatRepository implements ChatRepository {
 
 	@Override
 	public List<ChatMessage> getMessagesMatchingCriteria(Long before, Long after, Integer txGroupId, byte[] referenceBytes,
-			List<String> involving, Integer limit, Integer offset, Boolean reverse)
-			throws DataException {
+														 byte[] chatReferenceBytes, Boolean hasChatReference, List<String> involving, String senderAddress,
+														 Encoding encoding, Integer limit, Integer offset, Boolean reverse) throws DataException {
 		// Check args meet expectations
 		if ((txGroupId != null && involving != null && !involving.isEmpty())
 				|| (txGroupId == null && (involving == null || involving.size() != 2)))
@@ -35,7 +37,7 @@ public class HSQLDBChatRepository implements ChatRepository {
 
 		sql.append("SELECT created_when, tx_group_id, Transactions.reference, creator, "
 				+ "sender, SenderNames.name, recipient, RecipientNames.name, "
-				+ "data, is_text, is_encrypted, signature "
+				+ "chat_reference, data, is_text, is_encrypted, signature "
 				+ "FROM ChatTransactions "
 				+ "JOIN Transactions USING (signature) "
 				+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
@@ -62,6 +64,23 @@ public class HSQLDBChatRepository implements ChatRepository {
 			bindParams.add(referenceBytes);
 		}
 
+		if (chatReferenceBytes != null) {
+			whereClauses.add("chat_reference = ?");
+			bindParams.add(chatReferenceBytes);
+		}
+
+		if (hasChatReference != null && hasChatReference == true) {
+			whereClauses.add("chat_reference IS NOT NULL");
+		}
+		else if (hasChatReference != null && hasChatReference == false) {
+			whereClauses.add("chat_reference IS NULL");
+		}
+
+		if (senderAddress != null) {
+			whereClauses.add("sender = ?");
+			bindParams.add(senderAddress);
+		}
+
 		if (txGroupId != null) {
 			whereClauses.add("tx_group_id = " + txGroupId); // int safe to use literally
 			whereClauses.add("recipient IS NULL");
@@ -103,13 +122,14 @@ public class HSQLDBChatRepository implements ChatRepository {
 				String senderName = resultSet.getString(6);
 				String recipient = resultSet.getString(7);
 				String recipientName = resultSet.getString(8);
-				byte[] data = resultSet.getBytes(9);
-				boolean isText = resultSet.getBoolean(10);
-				boolean isEncrypted = resultSet.getBoolean(11);
-				byte[] signature = resultSet.getBytes(12);
+				byte[] chatReference = resultSet.getBytes(9);
+				byte[] data = resultSet.getBytes(10);
+				boolean isText = resultSet.getBoolean(11);
+				boolean isEncrypted = resultSet.getBoolean(12);
+				byte[] signature = resultSet.getBytes(13);
 
 				ChatMessage chatMessage = new ChatMessage(timestamp, groupId, reference, senderPublicKey, sender,
-						senderName, recipient, recipientName, data, isText, isEncrypted, signature);
+						senderName, recipient, recipientName, chatReference, encoding, data, isText, isEncrypted, signature);
 
 				chatMessages.add(chatMessage);
 			} while (resultSet.next());
@@ -121,7 +141,7 @@ public class HSQLDBChatRepository implements ChatRepository {
 	}
 
 	@Override
-	public ChatMessage toChatMessage(ChatTransactionData chatTransactionData) throws DataException {
+	public ChatMessage toChatMessage(ChatTransactionData chatTransactionData, Encoding encoding) throws DataException {
 		String sql = "SELECT SenderNames.name, RecipientNames.name "
 				+ "FROM ChatTransactions "
 				+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
@@ -141,33 +161,35 @@ public class HSQLDBChatRepository implements ChatRepository {
 			byte[] senderPublicKey = chatTransactionData.getSenderPublicKey();
 			String sender = chatTransactionData.getSender();
 			String recipient = chatTransactionData.getRecipient();
+			byte[] chatReference = chatTransactionData.getChatReference();
 			byte[] data = chatTransactionData.getData();
 			boolean isText = chatTransactionData.getIsText();
 			boolean isEncrypted = chatTransactionData.getIsEncrypted();
 			byte[] signature = chatTransactionData.getSignature();
 
 			return new ChatMessage(timestamp, groupId, reference, senderPublicKey, sender,
-					senderName, recipient, recipientName, data, isText, isEncrypted, signature);
+					senderName, recipient, recipientName, chatReference, encoding, data,
+					isText, isEncrypted, signature);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch convert chat transaction from repository", e);
 		}
 	}
 
 	@Override
-	public ActiveChats getActiveChats(String address) throws DataException {
-		List<GroupChat> groupChats = getActiveGroupChats(address);
+	public ActiveChats getActiveChats(String address, Encoding encoding) throws DataException {
+		List<GroupChat> groupChats = getActiveGroupChats(address, encoding);
 		List<DirectChat> directChats = getActiveDirectChats(address);
 
 		return new ActiveChats(groupChats, directChats);
 	}
 
-	private List<GroupChat> getActiveGroupChats(String address) throws DataException {
+	private List<GroupChat> getActiveGroupChats(String address, Encoding encoding) throws DataException {
 		// Find groups where address is a member and potential latest message details
-		String groupsSql = "SELECT group_id, group_name, latest_timestamp, sender, sender_name "
+		String groupsSql = "SELECT group_id, group_name, latest_timestamp, sender, sender_name, signature, data "
 				+ "FROM GroupMembers "
 				+ "JOIN Groups USING (group_id) "
 				+ "LEFT OUTER JOIN LATERAL("
-					+ "SELECT created_when AS latest_timestamp, sender, name AS sender_name "
+					+ "SELECT created_when AS latest_timestamp, sender, name AS sender_name, signature, data "
 					+ "FROM ChatTransactions "
 					+ "JOIN Transactions USING (signature) "
 					+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
@@ -191,8 +213,10 @@ public class HSQLDBChatRepository implements ChatRepository {
 
 					String sender = resultSet.getString(4);
 					String senderName = resultSet.getString(5);
+					byte[] signature = resultSet.getBytes(6);
+					byte[] data = resultSet.getBytes(7);
 
-					GroupChat groupChat = new GroupChat(groupId, groupName, timestamp, sender, senderName);
+					GroupChat groupChat = new GroupChat(groupId, groupName, timestamp, sender, senderName, signature, encoding, data);
 					groupChats.add(groupChat);
 				} while (resultSet.next());
 			}
@@ -201,7 +225,7 @@ public class HSQLDBChatRepository implements ChatRepository {
 		}
 
 		// We need different SQL to handle group-less chat
-		String grouplessSql = "SELECT created_when, sender, SenderNames.name "
+		String grouplessSql = "SELECT created_when, sender, SenderNames.name, signature, data "
 				+ "FROM ChatTransactions "
 				+ "JOIN Transactions USING (signature) "
 				+ "LEFT OUTER JOIN Names AS SenderNames ON SenderNames.owner = sender "
@@ -214,15 +238,19 @@ public class HSQLDBChatRepository implements ChatRepository {
 			Long timestamp = null;
 			String sender = null;
 			String senderName = null;
+			byte[] signature = null;
+			byte[] data = null;
 
 			if (resultSet != null) {
 				// We found a recipient-less, group-less CHAT message, so report its details
 				timestamp = resultSet.getLong(1);
 				sender = resultSet.getString(2);
 				senderName = resultSet.getString(3);
+				signature = resultSet.getBytes(4);
+				data = resultSet.getBytes(5);
 			}
 
-			GroupChat groupChat = new GroupChat(0, null, timestamp, sender, senderName);
+			GroupChat groupChat = new GroupChat(0, null, timestamp, sender, senderName, signature, encoding, data);
 			groupChats.add(groupChat);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch active group chats from repository", e);
@@ -277,4 +305,4 @@ public class HSQLDBChatRepository implements ChatRepository {
 		return directChats;
 	}
 
-}
+}

src/main/java/org/qortal/repository/hsqldb/HSQLDBDatabaseArchiving.java

@@ -1,88 +0,0 @@
-package org.qortal.repository.hsqldb;
-
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.qortal.controller.Controller;
-import org.qortal.gui.SplashFrame;
-import org.qortal.repository.BlockArchiveWriter;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.repository.RepositoryManager;
-import org.qortal.transform.TransformationException;
-
-import java.io.IOException;
-
-/**
- *
- * When switching to an archiving node, we need to archive most of the database contents.
- * This involves copying its data into flat files.
- * If we do this entirely as a background process, it is very slow and can interfere with syncing.
- * However, if we take the approach of doing this in bulk, before starting up the rest of the
- * processes, this makes it much faster and less invasive.
- *
- * From that point, the original background archiving process will run, but can be dialled right down
- * so not to interfere with syncing.
- *
- */
-
-
-public class HSQLDBDatabaseArchiving {
-
-    private static final Logger LOGGER = LogManager.getLogger(HSQLDBDatabaseArchiving.class);
-
-
-    public static boolean buildBlockArchive(Repository repository, long fileSizeTarget) throws DataException {
-
-        // Only build the archive if we haven't already got one that is up to date
-        boolean upToDate = BlockArchiveWriter.isArchiverUpToDate(repository);
-        if (upToDate) {
-            // Already archived
-            return false;
-        }
-
-        LOGGER.info("Building block archive - this process could take a while...");
-        SplashFrame.getInstance().updateStatus("Building block archive...");
-
-        final int maximumArchiveHeight = BlockArchiveWriter.getMaxArchiveHeight(repository);
-        int startHeight = 0;
-
-        while (!Controller.isStopping()) {
-            try {
-                BlockArchiveWriter writer = new BlockArchiveWriter(startHeight, maximumArchiveHeight, repository);
-                writer.setFileSizeTarget(fileSizeTarget);
-                BlockArchiveWriter.BlockArchiveWriteResult result = writer.write();
-                switch (result) {
-                    case OK:
-                        // Increment block archive height
-                        startHeight = writer.getLastWrittenHeight() + 1;
-                        repository.getBlockArchiveRepository().setBlockArchiveHeight(startHeight);
-                        repository.saveChanges();
-                        break;
-
-                    case STOPPING:
-                        return false;
-
-                    case NOT_ENOUGH_BLOCKS:
-                        // We've reached the limit of the blocks we can archive
-                        // Return from the whole method
-                        return true;
-
-                    case BLOCK_NOT_FOUND:
-                        // We tried to archive a block that didn't exist. This is a major failure and likely means
-                        // that a bootstrap or re-sync is needed. Return rom the method
-                        LOGGER.info("Error: block not found when building archive. If this error persists, " +
-                                "a bootstrap or re-sync may be needed.");
-                        return false;
-                }
-
-            } catch (IOException | TransformationException | InterruptedException e) {
-                LOGGER.info("Caught exception when creating block cache", e);
-                return false;
-            }
-        }
-
-        // If we got this far then something went wrong (most likely the app is stopping)
-        return false;
-    }
-
-}

src/main/java/org/qortal/repository/hsqldb/HSQLDBDatabasePruning.java

@@ -1,332 +0,0 @@
-package org.qortal.repository.hsqldb;
-
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.qortal.controller.Controller;
-import org.qortal.data.block.BlockData;
-import org.qortal.gui.SplashFrame;
-import org.qortal.repository.BlockArchiveWriter;
-import org.qortal.repository.DataException;
-import org.qortal.repository.Repository;
-import org.qortal.settings.Settings;
-
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.util.concurrent.TimeoutException;
-
-/**
- *
- * When switching from a full node to a pruning node, we need to delete most of the database contents.
- * If we do this entirely as a background process, it is very slow and can interfere with syncing.
- * However, if we take the approach of transferring only the necessary rows to a new table and then
- * deleting the original table, this makes the process much faster. It was taking several days to
- * delete the AT states in the background, but only a couple of minutes to copy them to a new table.
- *
- * The trade off is that we have to go through a form of "reshape" when starting the app for the first
- * time after enabling pruning mode. But given that this is an opt-in mode, I don't think it will be
- * a problem.
- *
- * Once the pruning is complete, it automatically performs a CHECKPOINT DEFRAG in order to
- * shrink the database file size down to a fraction of what it was before.
- *
- * From this point, the original background process will run, but can be dialled right down so not
- * to interfere with syncing.
- *
- */
-
-
-public class HSQLDBDatabasePruning {
-
-    private static final Logger LOGGER = LogManager.getLogger(HSQLDBDatabasePruning.class);
-
-
-    public static boolean pruneATStates(HSQLDBRepository repository) throws SQLException, DataException {
-
-        // Only bulk prune AT states if we have never done so before
-        int pruneHeight = repository.getATRepository().getAtPruneHeight();
-        if (pruneHeight > 0) {
-            // Already pruned AT states
-            return false;
-        }
-
-        if (Settings.getInstance().isArchiveEnabled()) {
-            // Only proceed if we can see that the archiver has already finished
-            // This way, if the archiver failed for any reason, we can prune once it has had
-            // some opportunities to try again
-            boolean upToDate = BlockArchiveWriter.isArchiverUpToDate(repository);
-            if (!upToDate) {
-                return false;
-            }
-        }
-
-        LOGGER.info("Starting bulk prune of AT states - this process could take a while... " +
-                "(approx. 2 mins on high spec, or upwards of 30 mins in some cases)");
-        SplashFrame.getInstance().updateStatus("Pruning database (takes up to 30 mins)...");
-
-        // Create new AT-states table to hold smaller dataset
-        repository.executeCheckedUpdate("DROP TABLE IF EXISTS ATStatesNew");
-        repository.executeCheckedUpdate("CREATE TABLE ATStatesNew ("
-                + "AT_address QortalAddress, height INTEGER NOT NULL, state_hash ATStateHash NOT NULL, "
-                + "fees QortalAmount NOT NULL, is_initial BOOLEAN NOT NULL, sleep_until_message_timestamp BIGINT, "
-                + "PRIMARY KEY (AT_address, height), "
-                + "FOREIGN KEY (AT_address) REFERENCES ATs (AT_address) ON DELETE CASCADE)");
-        repository.executeCheckedUpdate("SET TABLE ATStatesNew NEW SPACE");
-        repository.executeCheckedUpdate("CHECKPOINT");
-
-        // Add a height index
-        LOGGER.info("Adding index to AT states table...");
-        repository.executeCheckedUpdate("CREATE INDEX IF NOT EXISTS ATStatesNewHeightIndex ON ATStatesNew (height)");
-        repository.executeCheckedUpdate("CHECKPOINT");
-
-
-        // Find our latest block
-        BlockData latestBlock = repository.getBlockRepository().getLastBlock();
-        if (latestBlock == null) {
-            LOGGER.info("Unable to determine blockchain height, necessary for bulk block pruning");
-            return false;
-        }
-
-        // Calculate some constants for later use
-        final int blockchainHeight = latestBlock.getHeight();
-        int maximumBlockToTrim = blockchainHeight - Settings.getInstance().getPruneBlockLimit();
-        if (Settings.getInstance().isArchiveEnabled()) {
-            // Archive mode - don't prune anything that hasn't been archived yet
-            maximumBlockToTrim = Math.min(maximumBlockToTrim, repository.getBlockArchiveRepository().getBlockArchiveHeight() - 1);
-        }
-        final int endHeight = blockchainHeight;
-        final int blockStep = 10000;
-
-
-        // It's essential that we rebuild the latest AT states here, as we are using this data in the next query.
-        // Failing to do this will result in important AT states being deleted, rendering the database unusable.
-        repository.getATRepository().rebuildLatestAtStates();
-
-
-        // Loop through all the LatestATStates and copy them to the new table
-        LOGGER.info("Copying AT states...");
-        for (int height = 0; height < endHeight; height += blockStep) {
-            final int batchEndHeight = height + blockStep - 1;
-            //LOGGER.info(String.format("Copying AT states between %d and %d...", height, batchEndHeight));
-
-            String sql = "SELECT height, AT_address FROM LatestATStates WHERE height BETWEEN ? AND ?";
-            try (ResultSet latestAtStatesResultSet = repository.checkedExecute(sql, height, batchEndHeight)) {
-                if (latestAtStatesResultSet != null) {
-                    do {
-                        int latestAtHeight = latestAtStatesResultSet.getInt(1);
-                        String latestAtAddress = latestAtStatesResultSet.getString(2);
-
-                        // Copy this latest ATState to the new table
-                        //LOGGER.info(String.format("Copying AT %s at height %d...", latestAtAddress, latestAtHeight));
-                        try {
-                            String updateSql = "INSERT INTO ATStatesNew ("
-                                    + "SELECT AT_address, height, state_hash, fees, is_initial, sleep_until_message_timestamp "
-                                    + "FROM ATStates "
-                                    + "WHERE height = ? AND AT_address = ?)";
-                            repository.executeCheckedUpdate(updateSql, latestAtHeight, latestAtAddress);
-                        } catch (SQLException e) {
-                            repository.examineException(e);
-                            throw new DataException("Unable to copy ATStates", e);
-                        }
-
-                        // If this batch includes blocks after the maximum block to trim, we will need to copy
-                        // each of its AT states above maximumBlockToTrim as they are considered "recent". We
-                        // need to do this for _all_ AT states in these blocks, regardless of their latest state.
-                        if (batchEndHeight >= maximumBlockToTrim) {
-                            // Now copy this AT's states for each recent block they are present in
-                            for (int i = maximumBlockToTrim; i < endHeight; i++) {
-                                if (latestAtHeight < i) {
-                                    // This AT finished before this block so there is nothing to copy
-                                    continue;
-                                }
-
-                                //LOGGER.info(String.format("Copying recent AT %s at height %d...", latestAtAddress, i));
-                                try {
-                                    // Copy each LatestATState to the new table
-                                    String updateSql = "INSERT IGNORE INTO ATStatesNew ("
-                                            + "SELECT AT_address, height, state_hash, fees, is_initial, sleep_until_message_timestamp "
-                                            + "FROM ATStates "
-                                            + "WHERE height = ? AND AT_address = ?)";
-                                    repository.executeCheckedUpdate(updateSql, i, latestAtAddress);
-                                } catch (SQLException e) {
-                                    repository.examineException(e);
-                                    throw new DataException("Unable to copy ATStates", e);
-                                }
-                            }
-                        }
-                        repository.saveChanges();
-
-                    } while (latestAtStatesResultSet.next());
-                }
-            } catch (SQLException e) {
-                throw new DataException("Unable to copy AT states", e);
-            }
-        }
-
-
-        // Finally, drop the original table and rename
-        LOGGER.info("Deleting old AT states...");
-        repository.executeCheckedUpdate("DROP TABLE ATStates");
-        repository.executeCheckedUpdate("ALTER TABLE ATStatesNew RENAME TO ATStates");
-        repository.executeCheckedUpdate("ALTER INDEX ATStatesNewHeightIndex RENAME TO ATStatesHeightIndex");
-        repository.executeCheckedUpdate("CHECKPOINT");
-
-        // Update the prune height
-        int nextPruneHeight = maximumBlockToTrim + 1;
-        repository.getATRepository().setAtPruneHeight(nextPruneHeight);
-        repository.saveChanges();
-
-        repository.executeCheckedUpdate("CHECKPOINT");
-
-        // Now prune/trim the ATStatesData, as this currently goes back over a month
-        return HSQLDBDatabasePruning.pruneATStateData(repository);
-    }
-
-    /*
-     * Bulk prune ATStatesData to catch up with the now pruned ATStates table
-     * This uses the existing AT States trimming code but with a much higher end block
-     */
-    private static boolean pruneATStateData(Repository repository) throws DataException {
-
-        if (Settings.getInstance().isArchiveEnabled()) {
-            // Don't prune ATStatesData in archive mode
-            return true;
-        }
-
-        BlockData latestBlock = repository.getBlockRepository().getLastBlock();
-        if (latestBlock == null) {
-            LOGGER.info("Unable to determine blockchain height, necessary for bulk ATStatesData pruning");
-            return false;
-        }
-        final int blockchainHeight = latestBlock.getHeight();
-        int upperPrunableHeight = blockchainHeight - Settings.getInstance().getPruneBlockLimit();
-        // ATStateData is already trimmed - so carry on from where we left off in the past
-        int pruneStartHeight = repository.getATRepository().getAtTrimHeight();
-
-        LOGGER.info("Starting bulk prune of AT states data - this process could take a while... (approx. 3 mins on high spec)");
-
-        while (pruneStartHeight < upperPrunableHeight) {
-            // Prune all AT state data up until our latest minus pruneBlockLimit (or our archive height)
-
-            if (Controller.isStopping()) {
-                return false;
-            }
-
-            // Override batch size in the settings because this is a one-off process
-            final int batchSize = 1000;
-            final int rowLimitPerBatch = 50000;
-            int upperBatchHeight = pruneStartHeight + batchSize;
-            int upperPruneHeight = Math.min(upperBatchHeight, upperPrunableHeight);
-
-            LOGGER.trace(String.format("Pruning AT states data between %d and %d...", pruneStartHeight, upperPruneHeight));
-
-            int numATStatesPruned = repository.getATRepository().trimAtStates(pruneStartHeight, upperPruneHeight, rowLimitPerBatch);
-            repository.saveChanges();
-
-            if (numATStatesPruned > 0) {
-                LOGGER.trace(String.format("Pruned %d AT states data rows between blocks %d and %d",
-                        numATStatesPruned, pruneStartHeight, upperPruneHeight));
-            } else {
-                repository.getATRepository().setAtTrimHeight(upperBatchHeight);
-                // No need to rebuild the latest AT states as we aren't currently synchronizing
-                repository.saveChanges();
-                LOGGER.debug(String.format("Bumping AT states trim height to %d", upperBatchHeight));
-
-                // Can we move onto next batch?
-                if (upperPrunableHeight > upperBatchHeight) {
-                    pruneStartHeight = upperBatchHeight;
-                }
-                else {
-                    // We've finished pruning
-                    break;
-                }
-            }
-        }
-
-        return true;
-    }
-
-    public static boolean pruneBlocks(Repository repository) throws SQLException, DataException {
-
-        // Only bulk prune AT states if we have never done so before
-        int pruneHeight = repository.getBlockRepository().getBlockPruneHeight();
-        if (pruneHeight > 0) {
-            // Already pruned blocks
-            return false;
-        }
-
-        if (Settings.getInstance().isArchiveEnabled()) {
-            // Only proceed if we can see that the archiver has already finished
-            // This way, if the archiver failed for any reason, we can prune once it has had
-            // some opportunities to try again
-            boolean upToDate = BlockArchiveWriter.isArchiverUpToDate(repository);
-            if (!upToDate) {
-                return false;
-            }
-        }
-
-        BlockData latestBlock = repository.getBlockRepository().getLastBlock();
-        if (latestBlock == null) {
-            LOGGER.info("Unable to determine blockchain height, necessary for bulk block pruning");
-            return false;
-        }
-        final int blockchainHeight = latestBlock.getHeight();
-        int upperPrunableHeight = blockchainHeight - Settings.getInstance().getPruneBlockLimit();
-        int pruneStartHeight = 0;
-
-        if (Settings.getInstance().isArchiveEnabled()) {
-            // Archive mode - don't prune anything that hasn't been archived yet
-            upperPrunableHeight = Math.min(upperPrunableHeight, repository.getBlockArchiveRepository().getBlockArchiveHeight() - 1);
-        }
-
-        LOGGER.info("Starting bulk prune of blocks - this process could take a while... (approx. 5 mins on high spec)");
-
-        while (pruneStartHeight < upperPrunableHeight) {
-            // Prune all blocks up until our latest minus pruneBlockLimit
-
-            int upperBatchHeight = pruneStartHeight + Settings.getInstance().getBlockPruneBatchSize();
-            int upperPruneHeight = Math.min(upperBatchHeight, upperPrunableHeight);
-
-            LOGGER.info(String.format("Pruning blocks between %d and %d...", pruneStartHeight, upperPruneHeight));
-
-            int numBlocksPruned = repository.getBlockRepository().pruneBlocks(pruneStartHeight, upperPruneHeight);
-            repository.saveChanges();
-
-            if (numBlocksPruned > 0) {
-                LOGGER.info(String.format("Pruned %d block%s between %d and %d",
-                        numBlocksPruned, (numBlocksPruned != 1 ? "s" : ""),
-                        pruneStartHeight, upperPruneHeight));
-            } else {
-                final int nextPruneHeight = upperPruneHeight + 1;
-                repository.getBlockRepository().setBlockPruneHeight(nextPruneHeight);
-                repository.saveChanges();
-                LOGGER.debug(String.format("Bumping block base prune height to %d", nextPruneHeight));
-
-                // Can we move onto next batch?
-                if (upperPrunableHeight > nextPruneHeight) {
-                    pruneStartHeight = nextPruneHeight;
-                }
-                else {
-                    // We've finished pruning
-                    break;
-                }
-            }
-        }
-
-        return true;
-    }
-
-    public static void performMaintenance(Repository repository) throws SQLException, DataException {
-        try {
-            SplashFrame.getInstance().updateStatus("Performing maintenance...");
-
-            // Timeout if the database isn't ready for backing up after 5 minutes
-            // Nothing else should be using the db at this point, so a timeout shouldn't happen
-            long timeout = 5 * 60 * 1000L;
-            repository.performPeriodicMaintenance(timeout);
-
-        } catch (TimeoutException e) {
-            LOGGER.info("Attempt to perform maintenance failed due to timeout: {}", e.getMessage());
-        }
-    }
-
-}

src/main/java/org/qortal/repository/hsqldb/HSQLDBDatabaseUpdates.java

@@ -980,6 +980,19 @@ public class HSQLDBDatabaseUpdates {
 					stmt.execute("ALTER TABLE Accounts ADD blocks_minted_penalty INTEGER NOT NULL DEFAULT 0");
 					break;
 
+				case 45:
+					// Add a chat reference, to allow one message to reference another, and for this to be easily
+					// searchable. Null values are allowed as most transactions won't have a reference.
+					stmt.execute("ALTER TABLE ChatTransactions ADD chat_reference Signature");
+					// For finding chat messages by reference
+					stmt.execute("CREATE INDEX ChatTransactionsChatReferenceIndex ON ChatTransactions (chat_reference)");
+					break;
+
+				case 46:
+					// We need to track the sale price when canceling a name sale, so it can be put back when orphaned
+					stmt.execute("ALTER TABLE CancelSellNameTransactions ADD sale_price QortalAmount");
+					break;
+
 				default:
 					// nothing to do
 					return false;

src/main/java/org/qortal/repository/hsqldb/HSQLDBGroupRepository.java

@@ -777,9 +777,9 @@ public class HSQLDBGroupRepository implements GroupRepository {
 	}
 
 	@Override
-	public boolean banExists(int groupId, String offender) throws DataException {
+	public boolean banExists(int groupId, String offender, long timestamp) throws DataException {
 		try {
-			return this.repository.exists("GroupBans", "group_id = ? AND offender = ?", groupId, offender);
+			return this.repository.exists("GroupBans", "group_id = ? AND offender = ? AND (expires_when IS NULL OR expires_when > ?)", groupId, offender, timestamp);
 		} catch (SQLException e) {
 			throw new DataException("Unable to check for group ban in repository", e);
 		}

src/main/java/org/qortal/repository/hsqldb/HSQLDBMessageRepository.java

@@ -28,7 +28,6 @@ public class HSQLDBMessageRepository implements MessageRepository {
 		StringBuilder sql = new StringBuilder(1024);
 		sql.append("SELECT signature from MessageTransactions "
 				+ "JOIN Transactions USING (signature) "
-				+ "JOIN BlockTransactions ON transaction_signature = signature "
 				+ "WHERE ");
 
 		List<String> whereClauses = new ArrayList<>();

src/main/java/org/qortal/repository/hsqldb/transaction/HSQLDBArbitraryTransactionRepository.java

@@ -31,7 +31,7 @@ public class HSQLDBArbitraryTransactionRepository extends HSQLDBTransactionRepos
 
 			int version = resultSet.getInt(1);
 			int nonce = resultSet.getInt(2);
-			Service service = Service.valueOf(resultSet.getInt(3));
+			int serviceInt = resultSet.getInt(3);
 			int size = resultSet.getInt(4);
 			boolean isDataRaw = resultSet.getBoolean(5); // NOT NULL, so no null to false
 			DataType dataType = isDataRaw ? DataType.RAW_DATA : DataType.DATA_HASH;
@@ -44,7 +44,7 @@ public class HSQLDBArbitraryTransactionRepository extends HSQLDBTransactionRepos
 			ArbitraryTransactionData.Compression compression = ArbitraryTransactionData.Compression.valueOf(resultSet.getInt(12));
 
 			List<PaymentData> payments = this.getPaymentsFromSignature(baseTransactionData.getSignature());
-			return new ArbitraryTransactionData(baseTransactionData, version, service, nonce, size, name,
+			return new ArbitraryTransactionData(baseTransactionData, version, serviceInt, nonce, size, name,
 					identifier, method, secret, compression, data, dataType, metadataHash, payments);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch arbitrary transaction from repository", e);
@@ -66,7 +66,7 @@ public class HSQLDBArbitraryTransactionRepository extends HSQLDBTransactionRepos
 		HSQLDBSaver saveHelper = new HSQLDBSaver("ArbitraryTransactions");
 
 		saveHelper.bind("signature", arbitraryTransactionData.getSignature()).bind("sender", arbitraryTransactionData.getSenderPublicKey())
-				.bind("version", arbitraryTransactionData.getVersion()).bind("service", arbitraryTransactionData.getService().value)
+				.bind("version", arbitraryTransactionData.getVersion()).bind("service", arbitraryTransactionData.getServiceInt())
 				.bind("nonce", arbitraryTransactionData.getNonce()).bind("size", arbitraryTransactionData.getSize())
 				.bind("is_data_raw", arbitraryTransactionData.getDataType() == DataType.RAW_DATA).bind("data", arbitraryTransactionData.getData())
 				.bind("metadata_hash", arbitraryTransactionData.getMetadataHash()).bind("name", arbitraryTransactionData.getName())

src/main/java/org/qortal/repository/hsqldb/transaction/HSQLDBCancelSellNameTransactionRepository.java

@@ -17,15 +17,16 @@ public class HSQLDBCancelSellNameTransactionRepository extends HSQLDBTransaction
 	}
 
 	TransactionData fromBase(BaseTransactionData baseTransactionData) throws DataException {
-		String sql = "SELECT name FROM CancelSellNameTransactions WHERE signature = ?";
+		String sql = "SELECT name, sale_price FROM CancelSellNameTransactions WHERE signature = ?";
 
 		try (ResultSet resultSet = this.repository.checkedExecute(sql, baseTransactionData.getSignature())) {
 			if (resultSet == null)
 				return null;
 
 			String name = resultSet.getString(1);
+			Long salePrice = resultSet.getLong(2);
 
-			return new CancelSellNameTransactionData(baseTransactionData, name);
+			return new CancelSellNameTransactionData(baseTransactionData, name, salePrice);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch cancel sell name transaction from repository", e);
 		}
@@ -38,7 +39,7 @@ public class HSQLDBCancelSellNameTransactionRepository extends HSQLDBTransaction
 		HSQLDBSaver saveHelper = new HSQLDBSaver("CancelSellNameTransactions");
 
 		saveHelper.bind("signature", cancelSellNameTransactionData.getSignature()).bind("owner", cancelSellNameTransactionData.getOwnerPublicKey()).bind("name",
-				cancelSellNameTransactionData.getName());
+				cancelSellNameTransactionData.getName()).bind("sale_price", cancelSellNameTransactionData.getSalePrice());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qortal/repository/hsqldb/transaction/HSQLDBChatTransactionRepository.java

@@ -17,7 +17,7 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 	}
 
 	TransactionData fromBase(BaseTransactionData baseTransactionData) throws DataException {
-		String sql = "SELECT sender, nonce, recipient, is_text, is_encrypted, data FROM ChatTransactions WHERE signature = ?";
+		String sql = "SELECT sender, nonce, recipient, is_text, is_encrypted, data, chat_reference FROM ChatTransactions WHERE signature = ?";
 
 		try (ResultSet resultSet = this.repository.checkedExecute(sql, baseTransactionData.getSignature())) {
 			if (resultSet == null)
@@ -29,8 +29,9 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 			boolean isText = resultSet.getBoolean(4);
 			boolean isEncrypted = resultSet.getBoolean(5);
 			byte[] data = resultSet.getBytes(6);
+			byte[] chatReference = resultSet.getBytes(7);
 
-			return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, data, isText, isEncrypted);
+			return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, chatReference, data, isText, isEncrypted);
 		} catch (SQLException e) {
 			throw new DataException("Unable to fetch chat transaction from repository", e);
 		}
@@ -45,7 +46,7 @@ public class HSQLDBChatTransactionRepository extends HSQLDBTransactionRepository
 		saveHelper.bind("signature", chatTransactionData.getSignature()).bind("nonce", chatTransactionData.getNonce())
 				.bind("sender", chatTransactionData.getSender()).bind("recipient", chatTransactionData.getRecipient())
 				.bind("is_text", chatTransactionData.getIsText()).bind("is_encrypted", chatTransactionData.getIsEncrypted())
-				.bind("data", chatTransactionData.getData());
+				.bind("data", chatTransactionData.getData()).bind("chat_reference", chatTransactionData.getChatReference());
 
 		try {
 			saveHelper.execute(this.repository);

src/main/java/org/qortal/settings/Settings.java

@@ -110,7 +110,13 @@ public class Settings {
 	/** Maximum number of unconfirmed transactions allowed per account */
 	private int maxUnconfirmedPerAccount = 25;
 	/** Max milliseconds into future for accepting new, unconfirmed transactions */
-	private int maxTransactionTimestampFuture = 24 * 60 * 60 * 1000; // milliseconds
+	private int maxTransactionTimestampFuture = 30 * 60 * 1000; // milliseconds
+
+	/** Maximum number of CHAT transactions allowed per account in recent timeframe */
+	private int maxRecentChatMessagesPerAccount = 250;
+	/** Maximum age of a CHAT transaction to be considered 'recent' */
+	private long recentChatMessagesMaxAge = 60 * 60 * 1000L; // milliseconds
+
 	/** Whether we check, fetch and install auto-updates */
 	private boolean autoUpdateEnabled = true;
 	/** How long between repository backups (ms), or 0 if disabled. */
@@ -153,7 +159,7 @@ public class Settings {
 	 * This prevents the node from being able to serve older blocks */
 	private boolean topOnly = false;
 	/** The amount of recent blocks we should keep when pruning */
-	private int pruneBlockLimit = 1450;
+	private int pruneBlockLimit = 6000;
 
 	/** How often to attempt AT state pruning (ms). */
 	private long atStatesPruneInterval = 3219L; // milliseconds
@@ -172,6 +178,8 @@ public class Settings {
 	private boolean archiveEnabled = true;
 	/** How often to attempt archiving (ms). */
 	private long archiveInterval = 7171L; // milliseconds
+	/** Serialization version to use when building an archive */
+	private int defaultArchiveVersion = 1;
 
 
 	/** Whether to automatically bootstrap instead of syncing from genesis */
@@ -209,7 +217,7 @@ public class Settings {
 	public long recoveryModeTimeout = 10 * 60 * 1000L;
 
 	/** Minimum peer version number required in order to sync with them */
-	private String minPeerVersion = "3.8.0";
+	private String minPeerVersion = "3.8.7";
 	/** Whether to allow connections with peers below minPeerVersion
 	 * If true, we won't sync with them but they can still sync with us, and will show in the peers list
 	 * If false, sync will be blocked both ways, and they will not appear in the peers list */
@@ -267,7 +275,8 @@ public class Settings {
 	private String[] bootstrapHosts = new String[] {
 			"http://bootstrap.qortal.org",
 			"http://bootstrap2.qortal.org",
-			"http://62.171.190.193"
+			"http://bootstrap3.qortal.org",
+			"http://bootstrap.qortal.online"
 	};
 
 	// Auto-update sources
@@ -640,6 +649,14 @@ public class Settings {
 		return this.maxTransactionTimestampFuture;
 	}
 
+	public int getMaxRecentChatMessagesPerAccount() {
+		return this.maxRecentChatMessagesPerAccount;
+	}
+
+	public long getRecentChatMessagesMaxAge() {
+		return recentChatMessagesMaxAge;
+	}
+
 	public int getBlockCacheSize() {
 		return this.blockCacheSize;
 	}
@@ -912,6 +929,10 @@ public class Settings {
 		return this.archiveInterval;
 	}
 
+	public int getDefaultArchiveVersion() {
+		return this.defaultArchiveVersion;
+	}
+
 
 	public boolean getBootstrap() {
 		return this.bootstrap;

src/main/java/org/qortal/transaction/ArbitraryTransaction.java

@@ -9,6 +9,7 @@ import org.qortal.account.Account;
 import org.qortal.block.BlockChain;
 import org.qortal.controller.arbitrary.ArbitraryDataManager;
 import org.qortal.controller.arbitrary.ArbitraryDataStorageManager;
+import org.qortal.controller.repository.NamesDatabaseIntegrityCheck;
 import org.qortal.crypto.Crypto;
 import org.qortal.crypto.MemoryPoW;
 import org.qortal.data.PaymentData;
@@ -24,6 +25,7 @@ import org.qortal.transform.Transformer;
 import org.qortal.transform.transaction.ArbitraryTransactionTransformer;
 import org.qortal.transform.transaction.TransactionTransformer;
 import org.qortal.utils.ArbitraryTransactionUtils;
+import org.qortal.utils.NTP;
 
 public class ArbitraryTransaction extends Transaction {
 
@@ -34,9 +36,13 @@ public class ArbitraryTransaction extends Transaction {
 	public static final int MAX_DATA_SIZE = 4000;
 	public static final int MAX_METADATA_LENGTH = 32;
 	public static final int HASH_LENGTH = TransactionTransformer.SHA256_LENGTH;
-	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
 	public static final int MAX_IDENTIFIER_LENGTH = 64;
 
+	/** If time difference between transaction and now is greater than this then we don't verify proof-of-work. */
+	public static final long HISTORIC_THRESHOLD = 2 * 7 * 24 * 60 * 60 * 1000L;
+	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
+
+
 	// Constructors
 
 	public ArbitraryTransaction(Repository repository, TransactionData transactionData) {
@@ -82,6 +88,12 @@ public class ArbitraryTransaction extends Transaction {
 		if (this.transactionData.getFee() < 0)
 			return ValidationResult.NEGATIVE_FEE;
 
+		// After the feature trigger, we require the fee to be sufficient if it's not 0.
+		// If the fee is zero, then the nonce is validated in isSignatureValid() as an alternative to a fee
+		if (this.arbitraryTransactionData.getTimestamp() >= BlockChain.getInstance().getArbitraryOptionalFeeTimestamp() && this.arbitraryTransactionData.getFee() != 0L) {
+			return super.isFeeValid();
+		}
+
 		return ValidationResult.OK;
 	}
 
@@ -202,9 +214,15 @@ public class ArbitraryTransaction extends Transaction {
 			// Clear nonce from transactionBytes
 			ArbitraryTransactionTransformer.clearNonce(transactionBytes);
 
-			// Check nonce
-			int difficulty = ArbitraryDataManager.getInstance().getPowDifficulty();
-			return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
+			// As of feature-trigger timestamp, we only require a nonce when the fee is zero
+			boolean beforeFeatureTrigger = this.arbitraryTransactionData.getTimestamp() < BlockChain.getInstance().getArbitraryOptionalFeeTimestamp();
+			if (beforeFeatureTrigger || this.arbitraryTransactionData.getFee() == 0L) {
+				// We only need to check nonce for recent transactions due to PoW verification overhead
+				if (NTP.getTime() - this.arbitraryTransactionData.getTimestamp() < HISTORIC_THRESHOLD) {
+					int difficulty = ArbitraryDataManager.getInstance().getPowDifficulty();
+					return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
+				}
+			}
 		}
 
 		return true;
@@ -234,7 +252,15 @@ public class ArbitraryTransaction extends Transaction {
 
 	@Override
 	public void preProcess() throws DataException {
-		// Nothing to do
+		ArbitraryTransactionData arbitraryTransactionData = (ArbitraryTransactionData) transactionData;
+		if (arbitraryTransactionData.getName() == null)
+			return;
+
+		// Rebuild this name in the Names table from the transaction history
+		// This is necessary because in some rare cases names can be missing from the Names table after registration
+		// but we have been unable to reproduce the issue and track down the root cause
+		NamesDatabaseIntegrityCheck namesDatabaseIntegrityCheck = new NamesDatabaseIntegrityCheck();
+		namesDatabaseIntegrityCheck.rebuildName(arbitraryTransactionData.getName(), this.repository);
 	}
 
 	@Override

src/main/java/org/qortal/transaction/CancelGroupBanTransaction.java

@@ -73,7 +73,7 @@ public class CancelGroupBanTransaction extends Transaction {
 		Account member = getMember();
 
 		// Check ban actually exists
-		if (!this.repository.getGroupRepository().banExists(groupId, member.getAddress()))
+		if (!this.repository.getGroupRepository().banExists(groupId, member.getAddress(), this.groupUnbanTransactionData.getTimestamp()))
 			return ValidationResult.BAN_UNKNOWN;
 
 		// Check admin has enough funds

src/main/java/org/qortal/transaction/CancelSellNameTransaction.java

@@ -5,6 +5,7 @@ import java.util.List;
 
 import org.qortal.account.Account;
 import org.qortal.asset.Asset;
+import org.qortal.controller.repository.NamesDatabaseIntegrityCheck;
 import org.qortal.data.naming.NameData;
 import org.qortal.data.transaction.CancelSellNameTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -81,7 +82,13 @@ public class CancelSellNameTransaction extends Transaction {
 
 	@Override
 	public void preProcess() throws DataException {
-		// Nothing to do
+		CancelSellNameTransactionData cancelSellNameTransactionData = (CancelSellNameTransactionData) transactionData;
+
+		// Rebuild this name in the Names table from the transaction history
+		// This is necessary because in some rare cases names can be missing from the Names table after registration
+		// but we have been unable to reproduce the issue and track down the root cause
+		NamesDatabaseIntegrityCheck namesDatabaseIntegrityCheck = new NamesDatabaseIntegrityCheck();
+		namesDatabaseIntegrityCheck.rebuildName(cancelSellNameTransactionData.getName(), this.repository);
 	}
 
 	@Override

src/main/java/org/qortal/transaction/ChatTransaction.java

@@ -1,7 +1,9 @@
 package org.qortal.transaction;
 
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.function.Predicate;
 
 import org.qortal.account.Account;
 import org.qortal.account.PublicKeyAccount;
@@ -16,9 +18,11 @@ import org.qortal.list.ResourceListManager;
 import org.qortal.repository.DataException;
 import org.qortal.repository.GroupRepository;
 import org.qortal.repository.Repository;
+import org.qortal.settings.Settings;
 import org.qortal.transform.TransformationException;
 import org.qortal.transform.transaction.ChatTransactionTransformer;
 import org.qortal.transform.transaction.TransactionTransformer;
+import org.qortal.utils.NTP;
 
 public class ChatTransaction extends Transaction {
 
@@ -26,10 +30,11 @@ public class ChatTransaction extends Transaction {
 	private ChatTransactionData chatTransactionData;
 
 	// Other useful constants
-	public static final int MAX_DATA_SIZE = 1024;
+	public static final int MAX_DATA_SIZE = 4000;
 	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
-	public static final int POW_DIFFICULTY_WITH_QORT = 8; // leading zero bits
-	public static final int POW_DIFFICULTY_NO_QORT = 12; // leading zero bits
+	public static final int POW_DIFFICULTY_ABOVE_QORT_THRESHOLD = 8; // leading zero bits
+	public static final int POW_DIFFICULTY_BELOW_QORT_THRESHOLD = 18; // leading zero bits
+	public static final long POW_QORT_THRESHOLD = 400000000L;
 
 	// Constructors
 
@@ -78,7 +83,7 @@ public class ChatTransaction extends Transaction {
 		// Clear nonce from transactionBytes
 		ChatTransactionTransformer.clearNonce(transactionBytes);
 
-		int difficulty = this.getSender().getConfirmedBalance(Asset.QORT) > 0 ? POW_DIFFICULTY_WITH_QORT : POW_DIFFICULTY_NO_QORT;
+		int difficulty = this.getSender().getConfirmedBalance(Asset.QORT) >= POW_QORT_THRESHOLD ? POW_DIFFICULTY_ABOVE_QORT_THRESHOLD : POW_DIFFICULTY_BELOW_QORT_THRESHOLD;
 
 		// Calculate nonce
 		this.chatTransactionData.setNonce(MemoryPoW.compute2(transactionBytes, POW_BUFFER_SIZE, difficulty));
@@ -145,6 +150,11 @@ public class ChatTransaction extends Transaction {
 	public ValidationResult isValid() throws DataException {
 		// Nonce checking is done via isSignatureValid() as that method is only called once per import
 
+		// Disregard messages with timestamp too far in the future (we have stricter limits for CHAT transactions)
+		if (this.chatTransactionData.getTimestamp() > NTP.getTime() + (5 * 60 * 1000L)) {
+			return ValidationResult.TIMESTAMP_TOO_NEW;
+		}
+
 		// Check for blocked author by address
 		ResourceListManager listManager = ResourceListManager.getInstance();
 		if (listManager.listContains("blockedAddresses", this.chatTransactionData.getSender(), true)) {
@@ -163,6 +173,14 @@ public class ChatTransaction extends Transaction {
 			}
 		}
 
+		PublicKeyAccount creator = this.getCreator();
+		if (creator == null)
+			return ValidationResult.MISSING_CREATOR;
+
+		// Reject if unconfirmed pile already has X recent CHAT transactions from same creator
+		if (countRecentChatTransactionsByCreator(creator) >= Settings.getInstance().getMaxRecentChatMessagesPerAccount())
+			return ValidationResult.TOO_MANY_UNCONFIRMED;
+
 		// If we exist in the repository then we've been imported as unconfirmed,
 		// but we don't want to make it into a block, so return fake non-OK result.
 		if (this.repository.getTransactionRepository().exists(this.chatTransactionData.getSignature()))
@@ -204,7 +222,7 @@ public class ChatTransaction extends Transaction {
 
 		int difficulty;
 		try {
-			difficulty = this.getSender().getConfirmedBalance(Asset.QORT) > 0 ? POW_DIFFICULTY_WITH_QORT : POW_DIFFICULTY_NO_QORT;
+			difficulty = this.getSender().getConfirmedBalance(Asset.QORT) >= POW_QORT_THRESHOLD ? POW_DIFFICULTY_ABOVE_QORT_THRESHOLD : POW_DIFFICULTY_BELOW_QORT_THRESHOLD;
 		} catch (DataException e) {
 			return false;
 		}
@@ -213,6 +231,26 @@ public class ChatTransaction extends Transaction {
 		return MemoryPoW.verify2(transactionBytes, POW_BUFFER_SIZE, difficulty, nonce);
 	}
 
+	private int countRecentChatTransactionsByCreator(PublicKeyAccount creator) throws DataException {
+		List<TransactionData> unconfirmedTransactions = repository.getTransactionRepository().getUnconfirmedTransactions();
+		final Long now = NTP.getTime();
+		long recentThreshold = Settings.getInstance().getRecentChatMessagesMaxAge();
+
+		// We only care about chat transactions, and only those that are considered 'recent'
+		Predicate<TransactionData> hasSameCreatorAndIsRecentChat = transactionData -> {
+			if (transactionData.getType() != TransactionType.CHAT)
+				return false;
+
+			if (transactionData.getTimestamp() < now - recentThreshold)
+				return false;
+
+			return Arrays.equals(creator.getPublicKey(), transactionData.getCreatorPublicKey());
+		};
+
+		return (int) unconfirmedTransactions.stream().filter(hasSameCreatorAndIsRecentChat).count();
+	}
+
+
 	/**
 	 * Ensure there's at least a skeleton account so people
 	 * can retrieve sender's public key using address, even if all their messages

src/main/java/org/qortal/transaction/GroupInviteTransaction.java

@@ -78,7 +78,7 @@ public class GroupInviteTransaction extends Transaction {
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
 		// Check invitee is not banned
-		if (this.repository.getGroupRepository().banExists(groupId, invitee.getAddress()))
+		if (this.repository.getGroupRepository().banExists(groupId, invitee.getAddress(), this.groupInviteTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		// Check creator has enough funds

src/main/java/org/qortal/transaction/JoinGroupTransaction.java

@@ -53,7 +53,7 @@ public class JoinGroupTransaction extends Transaction {
 			return ValidationResult.ALREADY_GROUP_MEMBER;
 
 		// Check member is not banned
-		if (this.repository.getGroupRepository().banExists(groupId, joiner.getAddress()))
+		if (this.repository.getGroupRepository().banExists(groupId, joiner.getAddress(), this.joinGroupTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		// Check join request doesn't already exist

src/main/java/org/qortal/transaction/PublicizeTransaction.java

@@ -4,7 +4,9 @@ import java.util.Collections;
 import java.util.List;
 
 import org.qortal.account.Account;
+import org.qortal.account.PublicKeyAccount;
 import org.qortal.api.resource.TransactionsResource.ConfirmationStatus;
+import org.qortal.asset.Asset;
 import org.qortal.crypto.MemoryPoW;
 import org.qortal.data.transaction.PublicizeTransactionData;
 import org.qortal.data.transaction.TransactionData;
@@ -26,7 +28,7 @@ public class PublicizeTransaction extends Transaction {
 	/** If time difference between transaction and now is greater than this then we don't verify proof-of-work. */
 	public static final long HISTORIC_THRESHOLD = 2 * 7 * 24 * 60 * 60 * 1000L;
 	public static final int POW_BUFFER_SIZE = 8 * 1024 * 1024; // bytes
-	public static final int POW_DIFFICULTY = 15; // leading zero bits
+	public static final int POW_DIFFICULTY = 14; // leading zero bits
 
 	// Constructors
 
@@ -102,6 +104,12 @@ public class PublicizeTransaction extends Transaction {
 			if (!verifyNonce())
 				return ValidationResult.INCORRECT_NONCE;
 
+		// Validate fee if one has been included
+		PublicKeyAccount creator = this.getCreator();
+		if (this.transactionData.getFee() > 0)
+			if (creator.getConfirmedBalance(Asset.QORT) < this.transactionData.getFee())
+				return ValidationResult.NO_BALANCE;
+
 		return ValidationResult.OK;
 	}
 

src/main/java/org/qortal/transaction/RewardShareTransaction.java

@@ -163,9 +163,12 @@ public class RewardShareTransaction extends Transaction {
 				return ValidationResult.SELF_SHARE_EXISTS;
 		}
 
-		// Fee checking needed if not setting up new self-share
-		if (!(isRecipientAlsoMinter && existingRewardShareData == null))
-			// Check creator has enough funds
+		// Check creator has enough funds
+		if (this.rewardShareTransactionData.getTimestamp() >= BlockChain.getInstance().getFeeValidationFixTimestamp())
+			if (creator.getConfirmedBalance(Asset.QORT) < this.rewardShareTransactionData.getFee())
+				return ValidationResult.NO_BALANCE;
+
+		else if (!(isRecipientAlsoMinter && existingRewardShareData == null))
 			if (creator.getConfirmedBalance(Asset.QORT) < this.rewardShareTransactionData.getFee())
 				return ValidationResult.NO_BALANCE;
 

src/main/java/org/qortal/transaction/UpdateGroupTransaction.java

@@ -103,7 +103,7 @@ public class UpdateGroupTransaction extends Transaction {
 		Account newOwner = getNewOwner();
 
 		// Check new owner is not banned
-		if (this.repository.getGroupRepository().banExists(this.updateGroupTransactionData.getGroupId(), newOwner.getAddress()))
+		if (this.repository.getGroupRepository().banExists(this.updateGroupTransactionData.getGroupId(), newOwner.getAddress(), this.updateGroupTransactionData.getTimestamp()))
 			return ValidationResult.BANNED_FROM_GROUP;
 
 		return ValidationResult.OK;

src/main/java/org/qortal/transform/block/BlockTransformer.java

@@ -312,16 +312,24 @@ public class BlockTransformer extends Transformer {
 				ByteArrayOutputStream atHashBytes = new ByteArrayOutputStream(atBytesLength);
 				long atFees = 0;
 
-				for (ATStateData atStateData : block.getATStates()) {
-					// Skip initial states generated by DEPLOY_AT transactions in the same block
-					if (atStateData.isInitial())
-						continue;
+				if (block.getAtStatesHash() != null) {
+					// We already have the AT states hash
+					atFees = blockData.getATFees();
+					atHashBytes.write(block.getAtStatesHash());
+				}
+				else {
+					// We need to build the AT states hash
+					for (ATStateData atStateData : block.getATStates()) {
+						// Skip initial states generated by DEPLOY_AT transactions in the same block
+						if (atStateData.isInitial())
+							continue;
 
-					atHashBytes.write(atStateData.getATAddress().getBytes(StandardCharsets.UTF_8));
-					atHashBytes.write(atStateData.getStateHash());
-					atHashBytes.write(Longs.toByteArray(atStateData.getFees()));
+						atHashBytes.write(atStateData.getATAddress().getBytes(StandardCharsets.UTF_8));
+						atHashBytes.write(atStateData.getStateHash());
+						atHashBytes.write(Longs.toByteArray(atStateData.getFees()));
 
-					atFees += atStateData.getFees();
+						atFees += atStateData.getFees();
+					}
 				}
 
 				bytes.write(Ints.toByteArray(blockData.getATCount()));

src/main/java/org/qortal/transform/transaction/ArbitraryTransactionTransformer.java

@@ -7,7 +7,6 @@ import java.util.ArrayList;
 import java.util.List;
 
 import com.google.common.base.Utf8;
-import org.qortal.arbitrary.misc.Service;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.PaymentData;
 import org.qortal.data.transaction.ArbitraryTransactionData;
@@ -131,7 +130,7 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 				payments.add(PaymentTransformer.fromByteBuffer(byteBuffer));
 		}
 
-		Service service = Service.valueOf(byteBuffer.getInt());
+		int service = byteBuffer.getInt();
 
 		// We might be receiving hash of data instead of actual raw data
 		boolean isRaw = byteBuffer.get() != 0;
@@ -226,7 +225,7 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 			for (PaymentData paymentData : payments)
 				bytes.write(PaymentTransformer.toBytes(paymentData));
 
-			bytes.write(Ints.toByteArray(arbitraryTransactionData.getService().value));
+			bytes.write(Ints.toByteArray(arbitraryTransactionData.getServiceInt()));
 
 			bytes.write((byte) (arbitraryTransactionData.getDataType() == DataType.RAW_DATA ? 1 : 0));
 
@@ -299,7 +298,7 @@ public class ArbitraryTransactionTransformer extends TransactionTransformer {
 					bytes.write(PaymentTransformer.toBytes(paymentData));
 			}
 
-			bytes.write(Ints.toByteArray(arbitraryTransactionData.getService().value));
+			bytes.write(Ints.toByteArray(arbitraryTransactionData.getServiceInt()));
 
 			bytes.write(Ints.toByteArray(arbitraryTransactionData.getData().length));
 

src/main/java/org/qortal/transform/transaction/ChatTransactionTransformer.java

@@ -4,6 +4,7 @@ import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 
+import org.qortal.block.BlockChain;
 import org.qortal.crypto.Crypto;
 import org.qortal.data.transaction.BaseTransactionData;
 import org.qortal.data.transaction.ChatTransactionData;
@@ -22,11 +23,13 @@ public class ChatTransactionTransformer extends TransactionTransformer {
 	private static final int NONCE_LENGTH = INT_LENGTH;
 	private static final int HAS_RECIPIENT_LENGTH = BOOLEAN_LENGTH;
 	private static final int RECIPIENT_LENGTH = ADDRESS_LENGTH;
+	private static final int HAS_CHAT_REFERENCE_LENGTH = BOOLEAN_LENGTH;
+	private static final int CHAT_REFERENCE_LENGTH = SIGNATURE_LENGTH;
 	private static final int DATA_SIZE_LENGTH = INT_LENGTH;
 	private static final int IS_TEXT_LENGTH = BOOLEAN_LENGTH;
 	private static final int IS_ENCRYPTED_LENGTH = BOOLEAN_LENGTH;
 
-	private static final int EXTRAS_LENGTH = NONCE_LENGTH + HAS_RECIPIENT_LENGTH + DATA_SIZE_LENGTH + IS_ENCRYPTED_LENGTH + IS_TEXT_LENGTH;
+	private static final int EXTRAS_LENGTH = NONCE_LENGTH + HAS_RECIPIENT_LENGTH + DATA_SIZE_LENGTH + IS_ENCRYPTED_LENGTH + IS_TEXT_LENGTH + HAS_CHAT_REFERENCE_LENGTH;
 
 	protected static final TransactionLayout layout;
 
@@ -77,13 +80,24 @@ public class ChatTransactionTransformer extends TransactionTransformer {
 
 		long fee = byteBuffer.getLong();
 
+		byte[] chatReference = null;
+
+		if (timestamp >= BlockChain.getInstance().getChatReferenceTimestamp()) {
+			boolean hasChatReference = byteBuffer.get() != 0;
+
+			if (hasChatReference) {
+				chatReference = new byte[CHAT_REFERENCE_LENGTH];
+				byteBuffer.get(chatReference);
+			}
+		}
+
 		byte[] signature = new byte[SIGNATURE_LENGTH];
 		byteBuffer.get(signature);
 
 		BaseTransactionData baseTransactionData = new BaseTransactionData(timestamp, txGroupId, reference, senderPublicKey, fee, signature);
 
 		String sender = Crypto.toAddress(senderPublicKey);
-		return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, data, isText, isEncrypted);
+		return new ChatTransactionData(baseTransactionData, sender, nonce, recipient, chatReference, data, isText, isEncrypted);
 	}
 
 	public static int getDataLength(TransactionData transactionData) {
@@ -94,6 +108,9 @@ public class ChatTransactionTransformer extends TransactionTransformer {
 		if (chatTransactionData.getRecipient() != null)
 			dataLength += RECIPIENT_LENGTH;
 
+		if (chatTransactionData.getChatReference() != null)
+			dataLength += CHAT_REFERENCE_LENGTH;
+
 		return dataLength;
 	}
 
@@ -124,6 +141,16 @@ public class ChatTransactionTransformer extends TransactionTransformer {
 
 			bytes.write(Longs.toByteArray(chatTransactionData.getFee()));
 
+			if (transactionData.getTimestamp() >= BlockChain.getInstance().getChatReferenceTimestamp()) {
+				// Include chat reference if it's not null
+				if (chatTransactionData.getChatReference() != null) {
+					bytes.write((byte) 1);
+					bytes.write(chatTransactionData.getChatReference());
+				} else {
+					bytes.write((byte) 0);
+				}
+			}
+
 			if (chatTransactionData.getSignature() != null)
 				bytes.write(chatTransactionData.getSignature());
 

src/main/java/org/qortal/utils/BlockArchiveUtils.java

@@ -21,6 +21,16 @@ public class BlockArchiveUtils {
      * into the HSQLDB, in order to make it SQL-compatible
      * again.
      * <p>
+     * This is only fully compatible with archives that use
+     * serialization version 1. For version 2 (or above),
+     * we are unable to import individual AT states as we
+     * only have a single combined hash, so the use cases
+     * for this are greatly limited.
+     * <p>
+     * A version 1 archive should ultimately be rebuildable
+     * via a resync or reindex from genesis, allowing
+     * access to this feature once again.
+     * <p>
      * Note: calls discardChanges() and saveChanges(), so
      * make sure that you commit any existing repository
      * changes before calling this method.
@@ -61,9 +71,18 @@ public class BlockArchiveUtils {
                 repository.getBlockRepository().save(blockInfo.getBlockData());
 
                 // Save AT state data hashes
-                for (ATStateData atStateData : blockInfo.getAtStates()) {
-                    atStateData.setHeight(blockInfo.getBlockData().getHeight());
-                    repository.getATRepository().save(atStateData);
+                if (blockInfo.getAtStates() != null) {
+                    for (ATStateData atStateData : blockInfo.getAtStates()) {
+                        atStateData.setHeight(blockInfo.getBlockData().getHeight());
+                        repository.getATRepository().save(atStateData);
+                    }
+                }
+                else {
+                    // We don't have AT state hashes, so we are only importing a partial state.
+                    // This can still be useful to allow orphaning to very old blocks, when we
+                    // need to access other chainstate info (such as balances) at an earlier block.
+                    // In order to do this, the orphan process must be temporarily adjusted to avoid
+                    // orphaning AT states, as it will otherwise fail due to having no previous state.
                 }
 
             } catch (DataException e) {

src/main/resources/blockchain.json

@@ -83,8 +83,14 @@
 		"disableReferenceTimestamp": 1655222400000,
 		"increaseOnlineAccountsDifficultyTimestamp": 9999999999999,
 		"onlineAccountMinterLevelValidationHeight": 1092000,
-		"selfSponsorshipAlgoV1Height": 1092400
+		"selfSponsorshipAlgoV1Height": 1092400,
+		"feeValidationFixTimestamp": 1671918000000,
+		"chatReferenceTimestamp": 1674316800000,
+		"arbitraryOptionalFeeTimestamp": 1680278400000
 	},
+	"checkpoints": [
+		{ "height": 1136300, "signature": "3BbwawEF2uN8Ni5ofpJXkukoU8ctAPxYoFB7whq9pKfBnjfZcpfEJT4R95NvBDoTP8WDyWvsUvbfHbcr9qSZuYpSKZjUQTvdFf6eqznHGEwhZApWfvXu6zjGCxYCp65F4jsVYYJjkzbjmkCg5WAwN5voudngA23kMK6PpTNygapCzXt" }
+	],
 	"genesisInfo": {
 		"version": 4,
 		"timestamp": "1593450000000",

src/main/resources/i18n/ApiError_pl.properties

@@ -0,0 +1,83 @@
+#Generated by ResourceBundle Editor (http://essiembre.github.io/eclipse-rbe/)
+# Keys are from api.ApiError enum
+
+# "localeLang": "pl",
+
+### Common ###
+JSON = nie udało się przetworzyć wiadomości JSON
+
+INSUFFICIENT_BALANCE = niedostateczne środki
+
+UNAUTHORIZED = nieautoryzowane połączenie API
+
+REPOSITORY_ISSUE = błąd repozytorium
+
+NON_PRODUCTION = to wywołanie API nie jest dozwolone dla systemów produkcyjnych
+
+BLOCKCHAIN_NEEDS_SYNC = blockchain musi się najpierw zsynchronizować
+
+NO_TIME_SYNC = zegar się jeszcze nie zsynchronizował
+
+### Validation ###
+INVALID_SIGNATURE = nieprawidłowa sygnatura
+
+INVALID_ADDRESS = nieprawidłowy adres
+
+INVALID_PUBLIC_KEY = nieprawidłowy klucz publiczny
+
+INVALID_DATA = nieprawidłowe dane
+
+INVALID_NETWORK_ADDRESS = nieprawidłowy adres sieci
+
+ADDRESS_UNKNOWN = nieznany adres konta
+
+INVALID_CRITERIA = nieprawidłowe kryteria wyszukiwania
+
+INVALID_REFERENCE = nieprawidłowe skierowanie
+
+TRANSFORMATION_ERROR = nie udało się przekształcić JSON w transakcję
+
+INVALID_PRIVATE_KEY = klucz prywatny jest niepoprawny
+
+INVALID_HEIGHT = nieprawidłowa wysokość bloku
+
+CANNOT_MINT = konto nie możne bić monet
+
+### Blocks ###
+BLOCK_UNKNOWN = blok nieznany
+
+### Transactions ###
+TRANSACTION_UNKNOWN = nieznana transakcja
+
+PUBLIC_KEY_NOT_FOUND = nie znaleziono klucza publicznego
+
+# this one is special in that caller expected to pass two additional strings, hence the two %s
+TRANSACTION_INVALID = transakcja nieważna: %s (%s)
+
+### Naming ###
+NAME_UNKNOWN = nazwa nieznana
+
+### Asset ###
+INVALID_ASSET_ID = nieprawidłowy identyfikator aktywy
+
+INVALID_ORDER_ID = nieprawidłowy identyfikator zlecenia aktywy
+
+ORDER_UNKNOWN = nieznany identyfikator zlecenia aktywy
+
+### Groups ###
+GROUP_UNKNOWN = nieznana grupa
+
+### Foreign Blockchain ###
+FOREIGN_BLOCKCHAIN_NETWORK_ISSUE = obcy blockchain lub problem z siecią ElectrumX
+
+FOREIGN_BLOCKCHAIN_BALANCE_ISSUE = niewystarczające środki na obcym blockchainie
+
+FOREIGN_BLOCKCHAIN_TOO_SOON = zbyt wczesne nadawanie transakcji na obcym blockchainie (okres karencji/średni czas bloku)
+
+### Trade Portal ###
+ORDER_SIZE_TOO_SMALL = zbyt niska kwota zlecenia
+
+### Data ###
+FILE_NOT_FOUND = plik nie został znaleziony
+
+NO_REPLY = peer nie odpowiedział w wyznaczonym czasie

src/main/resources/i18n/ApiError_ru.properties

@@ -16,7 +16,7 @@ NON_PRODUCTION = этот вызов API не разрешен для произ
 
 BLOCKCHAIN_NEEDS_SYNC = блокчейн должен сначала синхронизироваться
 
-NO_TIME_SYNC = пока нет синхронизации часов
+NO_TIME_SYNC = время не синхронизировано
 
 ### Validation ###
 INVALID_SIGNATURE = недействительная подпись
@@ -72,7 +72,7 @@ FOREIGN_BLOCKCHAIN_NETWORK_ISSUE = проблема с внешним блокч
 
 FOREIGN_BLOCKCHAIN_BALANCE_ISSUE = недостаточный баланс на внешнем блокчейне
 
-FOREIGN_BLOCKCHAIN_TOO_SOON = слишком рано для трансляции транзакции во внений блокчей (время блокировки/среднее время блока)
+FOREIGN_BLOCKCHAIN_TOO_SOON = слишком рано для трансляции транзакции во внешний блокчей (время блокировки/среднее время блока)
 
 ### Trade Portal ###
 ORDER_SIZE_TOO_SMALL = слишком маленькая сумма ордера
@@ -80,4 +80,4 @@ ORDER_SIZE_TOO_SMALL = слишком маленькая сумма ордера
 ### Data ###
 FILE_NOT_FOUND = файл не найден
 
-NO_REPLY = узел не ответил данными
+NO_REPLY = нет ответа

src/main/resources/i18n/SysTray_de.properties

@@ -5,11 +5,11 @@ APPLYING_UPDATE_AND_RESTARTING = Automatisches Update anwenden und neu starten
 
 AUTO_UPDATE = Automatisches Update
 
-BLOCK_HEIGHT = height
+BLOCK_HEIGHT = Blockhöhe
 
 BLOCKS_REMAINING = blocks remaining
 
-BUILD_VERSION = Build-Version
+BUILD_VERSION = Entwicklungs-Version
 
 CHECK_TIME_ACCURACY = Prüfe Zeitgenauigkeit
 
@@ -23,7 +23,7 @@ CREATING_BACKUP_OF_DB_FILES = Erstellen Backup von Datenbank Dateien …
 
 DB_BACKUP = Datenbank Backup
 
-DB_CHECKPOINT = Datenbank Kontrollpunkt
+DB_CHECKPOINT = Datenbank Check
 
 DB_MAINTENANCE = Datenbank Instandhaltung
 
@@ -31,18 +31,18 @@ EXIT = Verlassen
 
 LITE_NODE = Lite node
 
-MINTING_DISABLED = NOT minting
+MINTING_DISABLED = Kein minting
 
-MINTING_ENABLED = \u2714 Minting
+MINTING_ENABLED = \u2714 Minting aktiviert 
 
 OPEN_UI = Öffne UI
 
-PERFORMING_DB_CHECKPOINT = Speichern nicht übergebener Datenbank Änderungen …
+PERFORMING_DB_CHECKPOINT = Speichern von unbestätigten Datenbankänderungen...
 
 PERFORMING_DB_MAINTENANCE = Planmäßige Wartung durchführen...
 
 SYNCHRONIZE_CLOCK = Synchronisiere Uhr
 
-SYNCHRONIZING_BLOCKCHAIN = Synchronisierung
+SYNCHRONIZING_BLOCKCHAIN = Synchronisierung der Blockchain
 
-SYNCHRONIZING_CLOCK = Synchronisierung Uhr
+SYNCHRONIZING_CLOCK = Synchronisierung der Uhr