Hello, On my laptop firefox cpu usage spikes to 100% when trying to play an html5 video on youtube, the situation is slightly better on other sites but still the load never goes under 80%, this is on -current on a GM45 intel chipset if it matters.
Generally speaking it has the worst performance when playing html5 videos, I've tried chromium , xombrero and midori and they all work fine while firefox playback is choppy when it's at his best else it just saturates the cpu and freezes the browser. No output or errors are disaplyed when unsing firefox started from a terminal. Claudio