When I covered 3/4 of the banner, the CPU usage was about 12-13% (a quarter of 50%), and when covered only 1/4 of the FF3 banner, the usage was around 37-38% (three quarters of 50%). Then I tried to cover only half of the banner in FF3 and guess what, CPU usage was 25%. Then I grabbed the standalone flash player window and dragged it OVER the FF3 banner - and VIOLA! - CPU usage 1%! - with all windows open - including the FF3 window. In the next step, I opened up all the windows at same time (FF3,IE6,flash) and distributed them on the screen so all were visible, which gave a total of 50% CPU usage.

Viewed in Flash standalone player = 1% CPU usage. When viewed with FF3, the CPU usage was constant 50%. One of my tests included a simple animated flash banner on a blank html page. After some testing and seeing that same CPU usage issues occur with Java based image scrolling ( ) I have came to a conclusion that all these problems might be related to some buggy graphics display code in FF3. I am experiencing same problems with flash in FF3.

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