Only clean up messages while active

// FREEBIE

SignalServiceKit/src/Messages/OWSDisappearingMessagesJob.m

@@ -364,6 +364,10 @@ void AssertIsOnDisappearingMessagesQueue()
     }
 
     dispatch_async(OWSDisappearingMessagesJob.serialQueue, ^{
+        if (!CurrentAppContext().isMainAppAndActive) {
+            DDLogInfo(@"%@ Ignoring fallbacktimer for app which is not main and active.", self.logTag);
+            return;
+        }
         NSUInteger deletedCount = [self runLoop];
 
         // Normally deletions should happen via the disappearanceTimer, to make sure that they're prompt.