When I play a HTML5 video on youtube (both https://www.youtube.com/html5 and a right click on the video show that HTML5 is used) with chromium the cpu usage goes to 100% on all cores caused by libpepflashplayer.so.
Is youtube just pretending to be using HTML5 and actually uses flash or is there something else going on (i.e. what tests can I perform to troubleshoot)?
High cpu load is also the case with firefox, but in that case there is no separate process for the flash-plugin, so I have no indication whether flash is involved.