Could also be related to an issue with Lemmy’s websockets. Having multiple Lemmy.world tabs open does cause some weird issues. Like sometimes you will see posts from different communities, or the sidebar can be from another community. Things like that.

I heard they are working on a fix but I’ll have to go browse Lemmy’s GitHub get some more factual information.

I’ve seen this issue a few times. To my knowledge this is purely a visual bug and should be fixed soon enough. I’ll have to look for the link to the post from one of the devs.