This is a "but it works on my machine" one and could be tricky:
I have a lightbox-style HTML dialog that shows a menu on top of a web page. It can be injected into any web page via a JavaScript bookmarklet.
One of my users is trying to use it on YouTube.com with the result that the flash movie is rendered on top of the dialog (a div with high z-index).
I can't reproduce this. It works just fine for me. The dialog shows up on top of everything else on youtube.com, the video included.
I had him save the page in Safari as Webarchive and send it to me. Even that shows the menu rendered correctly for me.
I use the exact same version of Safari (4.0.5/531.22.7) and Flash (10.1 r53, latest beta). Only difference I could find is that he uses Snow Leopard (10.6.6) and I "only" 10.5.8.
Has anybody noticed similar problems? I'm afraid that the usual wmode recommendation won't solve this (I tried & it works on my machine anyway)...
Thanks! Mark