Debug

Signal/src/ViewControllers/ConversationView/Cells/OWSMessageBubbleView.m

@@ -717,7 +717,16 @@ NS_ASSUME_NONNULL_BEGIN
             NSString *userID = [[text substringWithRange:match1.range] stringByReplacingCharactersInRange:NSMakeRange(0, 1) withString:@""];
             NSUInteger matchEnd;
             if ([knownUserIDs containsObject:userID]) {
-                NSString *userDisplayName = [Environment.shared.contactsManager attributedContactOrProfileNameForPhoneIdentifier:userID primaryFont:font secondaryFont:font].string;
+                __block NSString *userDisplayName = [Environment.shared.contactsManager attributedContactOrProfileNameForPhoneIdentifier:userID primaryFont:font secondaryFont:font].string;
+                if ([userDisplayName isEqual:userID]) {
+                    [OWSPrimaryStorage.sharedManager.dbReadConnection readWithBlock:^(YapDatabaseReadTransaction *transaction) {
+                        NSString *collection = [NSString stringWithFormat:@"%@.%llu", LKGroupChatAPI.publicChatServer, LKGroupChatAPI.publicChatServerID];
+                        NSString *userDisplayNameCandidate = [transaction objectForKey:userID inCollection:collection];
+                        if (userDisplayNameCandidate != nil) {
+                            userDisplayName = userDisplayNameCandidate;
+                        }
+                    }];
+                }
                 text = [text stringByReplacingCharactersInRange:match1.range withString:[NSString stringWithFormat:@"@%@", userDisplayName]];
                 [mentions addObject:[NSValue valueWithRange:NSMakeRange(match1.range.location, userDisplayName.length + 1)]];
                 matchEnd = match1.range.location + userDisplayName.length;

Signal/src/ViewControllers/ConversationView/ConversationViewController.m

@@ -524,7 +524,7 @@ typedef enum : NSUInteger {
                                                           userInfo:nil
                                                            repeats:YES];
     
-    [LKAPI populateUserIDCacheIfNeededFor:thread.uniqueId];
+    [LKAPI populateUserIDCacheIfNeededFor:thread.uniqueId in:nil];
 }
 
 - (void)dealloc

SignalServiceKit/src/Loki/API/LokiAPI.swift

@@ -306,10 +306,10 @@ public final class LokiAPI : NSObject {
         }
     }
     
-    @objc public static func populateUserIDCacheIfNeeded(for threadID: String) {
+    @objc public static func populateUserIDCacheIfNeeded(for threadID: String, in transaction: YapDatabaseReadWriteTransaction? = nil) {
         guard userIDCache[threadID] == nil else { return }
         var result: Set<String> = []
-        storage.dbReadWriteConnection.readWrite { transaction in
+        func populate(in transaction: YapDatabaseReadWriteTransaction) {
             guard let thread = TSThread.fetch(uniqueId: threadID, transaction: transaction) else { return }
             let interactions = transaction.ext(TSMessageDatabaseViewExtensionName) as! YapDatabaseViewTransaction
             interactions.enumerateKeysAndObjects(inGroup: threadID) { _, _, object, index, _ in
@@ -317,6 +317,13 @@ public final class LokiAPI : NSObject {
                 result.insert(message.authorId)
             }
         }
+        if let transaction = transaction {
+            populate(in: transaction)
+        } else {
+            storage.dbReadWriteConnection.readWrite { transaction in
+                populate(in: transaction)
+            }
+        }
         result.insert(userHexEncodedPublicKey)
         userIDCache[threadID] = result
     }

SignalServiceKit/src/Messages/OWSMessageManager.m

@@ -1412,9 +1412,9 @@ NS_ASSUME_NONNULL_BEGIN
                         (unsigned long)timestamp);
                     return nil;
                 }
-
+                
                 // Loki: Cache the user hex encoded public key (for mentions)
-                [LKAPI populateUserIDCacheIfNeededFor:oldGroupThread.uniqueId];
+                [LKAPI populateUserIDCacheIfNeededFor:oldGroupThread.uniqueId in:transaction];
                 [LKAPI cache:incomingMessage.authorId for:oldGroupThread.uniqueId];
                 
                 [self finalizeIncomingMessage:incomingMessage