(In reply to comment #4)
> Yes, Twitch, like YouTube, requires Flash.

Actually, YouTube doesn't require Flash, at least not for many videos.

> > Does doing anything in particular trigger it in MediathekView?
> 
> Sort of: just starting is enough. You get the grey window background at
> below average speed and then it takes seconds until the UI elements are
> drawn (list of shows, filter boxes, buttons). Afterwards you can trigger a
> new CPU spike by trying to click anything or even better on each
> keypress/character input into the title filter field on the left.

I can reproduce this with glamor from xserver 1.16.0, but not from current
xserver Git master. So at least that part is already fixed.