[jpeloquin]

The upvote and downvote buttons are a couple millimeters apart on mobile and there's no feedback (that I've noticed, anyway) regarding which one you've pressed. There's probably a lot of accidental voting.

[hulahoof]

After you hit one of them, an 'undown' or 'unvote' button appears in front of the 'root' / 'parent' button

[card_zero]

Oh it says "undown", that's good to know, I often worry I might have downvoted somebody by mistake. (Never done it deliberately.)

[fourthark]

The vote button you press disappears, as well. I think this depends on some kind of local storage; it's often slightly out of sync.