The first one I haven't seen yet (although I didn't look too hard on here) but nonetheless is quite annoying. Its not game breaking but it does mess me up a bit. Often when selecting anything in a list such as an item to sell/buy or an instance to go to, randomly it seems, the list selects one down. This is with no interaction from me as far as I can tell, and I've checked all my bindings/mouse keys that could do this and cant figure out why.
The other issue I have is with targeting. Tab targeting works fine, but when I manually click on a target sometimes it decides to constantly re target something else. Again, I am not certain why, it seems sometimes it happens when something is behind me and usually ends up targeting a group like "Allies " or "Enemies " Can be quite annoying and has caused me to give up on clicking to target almost anything at all.