fix: use irc-unknown when irc server couldn't be loaded (#5419)

CHANGELOG.md

@@ -8,6 +8,7 @@
 - Minor: Colored usernames now update on the fly when changing the "Color @usernames" setting. (#5300)
 - Minor: Added `flags.action` filter variable, allowing you to filter on `/me` messages. (#5397)
 - Bugfix: If a network request errors with 200 OK, Qt's error code is now reported instead of the HTTP status. (#5378)
+- Bugfix: Fixed a crash that could occur when logging was enabled in IRC servers that were removed. (#5419)
 - Dev: Use Qt's high DPI scaling. (#4868, #5400)
 - Dev: Add doxygen build target. (#5377)
 - Dev: Make printing of strings in tests easier. (#5379)

src/common/Channel.cpp

@@ -92,8 +92,16 @@ void Channel::addMessage(MessagePtr message,
             auto *irc = dynamic_cast<IrcChannel *>(this);
             if (irc != nullptr)
             {
-                channelPlatform = QString("irc-%1").arg(
-                    irc->server()->userFriendlyIdentifier());
+                auto *ircServer = irc->server();
+                if (ircServer != nullptr)
+                {
+                    channelPlatform = QString("irc-%1").arg(
+                        irc->server()->userFriendlyIdentifier());
+                }
+                else
+                {
+                    channelPlatform = "irc-unknown";
+                }
             }
         }
         else if (this->isTwitchChannel())