public async void LoadPinnedTopics()
 {
     if (_pinnedTopicsLoaded)
     {
         return;
     }
     _pinnedTopicsLoaded = true;
     foreach (var item in (await ResourceLocator.DataCacheService.RetrieveDataRoaming <List <ForumTopicLightEntry> >("pinned_forum_topics.json", -1)) ?? new List <ForumTopicLightEntry>())
     {
         PinnedTopics.Add(item);
     }
 }
 public async Task SavePinnedTopics()
 {
     await ResourceLocator.DataCacheService.SaveDataRoaming(PinnedTopics.ToList(), "pinned_forum_topics.json");
 }