i can't view html5 video , because firefox begins to slow. with flash player i don't have this problem, all works perfect. but youtube and other sites use html5 player, and i need switch browser to Chrome for good viewing. How i can fix very bad working FF with html5 video? i have a laptop with 12gb ram,corei7 and geforce740m and i have big lags when i view html video. When i push play the video, all open pages and the entire program have big lags. very lucky if i can close tab with video :/ and dont need kill ff proccess. Please help! I dont want use the Chrome and other browsers...