I have found that for me it is only lemmy.ml communities. When I was on lemmy.ml it always happened. I moved to lemmy.world and now it is only lemmy.ml communities that do it. Desktop or mobile. It's an instance problem, not a jerboa problem from what I can tell.
This happens to me on lemmy.world as well, not using the app, curious that your move fixed it though. I think it might be a general lemmy issue rather than instance specific
Yeah this is why I'm asking because I've noticed it happens across multiple different instances. If it's a known issue then eh whatever I hope they fix it but it's still quite annoying.