Report YouTube HTML5 Fullscreen performance in Archived General Discussion Posted February 23, 2015 Hi, For some reason when I try to view YouTube video in fullscreen while using HTML5 player, it appears to run at something like 10 frames per second. When not in fullscreen or while using Flash player, it plays smoothly. I tried Firefox and there is no problem there. I also tried reinstalling Maxthon without success. Any tips?