I just now observed that this CPU spike only happens when I have https://www.blogger.com/start (the German version) open in Firefox (2.0.0.10). I guess it's a Firefox <-> Xorg (<-> Compiz) problem. As I only opened this page after upgrading Compiz, this problem is most likely NOT related to Compiz at all.
Sorry, totally wrong description.
I just now observed that this CPU spike only happens when I have https:/ /www.blogger. com/start (the German version) open in Firefox (2.0.0.10). I guess it's a Firefox <-> Xorg (<-> Compiz) problem. As I only opened this page after upgrading Compiz, this problem is most likely NOT related to Compiz at all.