I just upgraded from Ubuntu Hardy to Ubuntu Intrepid. As always – there is something totally wrong going on after an upgrade. My network didn’t work anymore (solved, because of openvpn created wrong routes), my sound was flaky because of pulseaudio (just turned it off) and Flash applets in Firefox were flickering.
I solved the latter problem now, by just using the Firefox 3 from Ubuntu. I had a local installed Firefox 3 which was probably older than the version in Ubuntu. That solved the problem and flash applets aren’t flickering anymore.