chasx yeah, you're experiencing a rare Flarum bug that seems to be stuck to you for some reason lol clear your cache as previously suggested. I'm sure everyone else here can see your posts, but there is a Flarum bug that's still existent that shows some posts as [deleted] which eventually does go away after you clear your browser cache.
98% of Flarum issues stem from cache issues, which become less frequent over release cycles, so we all have to clean our caches, even from Flarum itself on our server lol
