Ensure tags of threads work consistently

#tags of threads often show up as #deleted-channel despite the thread existing.

ETA:

Additionally, after updating the mobile app to "140.21 (null) googleRelease" (I believe this signifies the app version), now any time I edit a post with thread tags, the tags break.

In the previous app version, thread tags showed up as <#threadID> in editing mode, and didn't break when saving. Now they show up as "Thread Name", and when the edit is saved, the tag breaks, showing up as "Thread Name" in the edited post as well.