If it is a corrupted file somewhere it should not affect other forums (especially if it is this forum's server, perhaps interacting with a faulty cache on yours). Do the other forums have the same Themes? (Not that I suggest playing around with other forums necessarily as they might corrupt also.)
Are you running some kind of backup or something on your devices or router that might change a cache (or not?)
You did not say you tried changing the Theme a few times when you discovered it this time. Did you? I presume it does not work?
Does the problem show on all other devices still?
Check that other new user you made. Has it changed on there also?
Are you running some kind of backup or something on your devices or router that might change a cache (or not?)
You did not say you tried changing the Theme a few times when you discovered it this time. Did you? I presume it does not work?
Does the problem show on all other devices still?
Check that other new user you made. Has it changed on there also?