[zenocon]

I'm running adobe's FP 10.0.45.2. When you hit a site that requires flash the first time, firefox prompts you to install the plugin, and it gives you three options: the adobe player, and two other oss versions. I chose the adobe player.

Based on your query, I went back and tried to see if I could stress it out. I tried this site from a simple google search for 'flash demo' http://www.playpuzzlequestgalactrix.com/ and it works fine for me...no issues. This one, however: http://ecodazoo.com/ is pretty intense, and it does flicker for me. Normally, I don't visit sites like that which are all flash intensive, thus my comment that I rarely ever see an issue with FP on Ubuntu x64...but indeed, it is not perfect.