I filed a few reports when I started playing a year ago, but since it hasn't been fixed yet, here:

Sometimes after I use a vial I'll open up the chat window and discover that I'm suddenly spamming 22222222222222 or 33333333333333333333333333 or 444444444444444444444444444444 or 3444444433343333434343434343444443344444. It's REALLY inconvenient when in the middle of a battle and trying to communicate. I can make it stop by entering and exiting fullscreen, but that's tape slapped over the leak, not an actual solution. (Not to mention time consuming and it makes my laptop slow waaaaayyyyyy down for a few minutes.) I haven't been able to find any sort of commonality when it happens, either.