Hi, I'm using Iceweasel on my Debian 8 and it has a very annoying bug: whenever I replay a video, it plays all glitched. The first time it plays fine, but when it replays it's all pixelated! The glitch always happens, even if I replay a video on youtube (if I return to the beggining of the video without it reaching the end, no bug happens) or html5 videos on background of sites, or even gifs (which are mp4 videos) on twitter. I've searched google but I can't find ANY information about this at all. Somebody knows what might be the problem? Chromium runs fine without such glitch.