Conversation.setMarkedUnread: Only captureChange if value changed

ts/models/conversations.ts

@@ -3049,9 +3049,15 @@ export class ConversationModel extends window.Backbone.Model<
   }
 
   setMarkedUnread(markedUnread: boolean): void {
+    const previousMarkedUnread = this.get('markedUnread');
+
     this.set({ markedUnread });
     window.Signal.Data.updateConversation(this.attributes);
-    this.captureChange('markedUnread');
+
+    if (Boolean(previousMarkedUnread) !== Boolean(markedUnread)) {
+      this.captureChange('markedUnread');
+    }
+
     window.Whisper.events.trigger('updateUnreadCount');
   }