This can happen if the server hangs on the page request. It should eventually either load or time out and show a message at the bottom to try again though.
Ah, that sounds like an old Lemmy glitch. I’m not sure what causes it. If you could do a screen recording I could confirm. Also you can check Lemmy-ui or other apps (with same account) to confirm.
If you can find the exact version that it started happening, and exact reproduction steps that would be helpful since I haven't seen what you're describing.
Hooray!