I havent seen a thread for this, report common bugs here

1. Warping often makes you and mobs invisible until you relog, you can tell if you're invisible by pressing F5, if you cannot see your skin you are bugged and need to relog else other players cannot see you, you cannot affect pressure plates and ing eneral weird stuff will happen if you dont

2. Some odd "lag" type issues (like reappearing blocks) i tried removing some torches and the torch reappeared like twice but dropped the item each time still so it kind of duped it

Add more (no posting pointless crap, keep it official)