There's a threshold, the exact number I haven't figured out yet, where connect has trouble with multiple accounts.
I have what is lovingly called "the bathroom tablet" that's there for guests. Yesterday, a fairly decent sized group was over, and they've made the migration to lemmy, so connect now has a dozen accounts on it.
Switching between them causes each account to be "lost", where you switch, and the account you're switching to is not logged in, and the one you switched from is now logged out.
Edit: the threshold seems to be around five or six accounts. At least, that's where the behavior stopped after a few experiments. Five doesn't do it at all, six only does it maybe 1/10 tries.
Haven't had a chance to sit down with the guys and try to whittle the list down to see what the threshold is yet. Don't have their login info, so there's no point yet