Steps to reproduce:
1) Visit http://inhabitat.com/2010/06/29/university-of-michigan-solar-car-team-wins-american-solar-challenge/
2) Scroll down below the header of the page
3) Let the page sit for a few minutes
4) Scroll back up, the header is gone.
I cannot reproduce this with Safari 5.0 on Snow Leopard.
Could you please describe your configuration (OS, Safari and Flash versions, 64 bit or 32 bit)? Is this reliably reproducible? Does this happen with Flash disabled?
After investigating further, this problem seems to involve plugins. It is unnecessary to scroll down on the page to cause the header to disappear. Disabling plugins seems to cause the problem to go away. After the header has disappeared, if you turn plugins off, the header will reappear, and then disappear when plugins are turned back on.
I'm running 64bit Safari 5.0 on Snow Leopard. It seems to alternate between the entire header disappearing, and just the logo in the upper left disappearing. I have also confirmed that the problem exists on the r62241 nightly build for Snow Leopard.
The version of flash that I am running (http://kb2.adobe.com/cps/155/tn_15507.html) is 10,1,53,64.
Does this happen with TOT?
Running on a debug build of revision 62596 (2010-07-06 14:21:37), the problem still seems to occur.
Created attachment 76601 [details]
Comment on attachment 76601 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=76601&action=review
Since this test involves video (and it looks like a plugin is required to tickle the bug), shouldn't it have plugin or video in the name?
> + return didAnimateTransform || didAnimateOpacity;
Yeah, much better logic