Regarding the arrow, what arrow are you referring to for collapsing a thread? There's no arrow for collapsing. You collapse comments by tapping on them. The arrow on the comment is for up voting which can also be done by swiping on a comment. Am I misunderstanding the issue?
Actually I think you are right too. I think it has to do with the upvote button’s hit area being too small so sometimes it overflows to outside the button and collapses the thread instead. I will see what I can do to fix it.
