Safari is NOT frozen, can click on page, but will not show as topmost app
I typically have many pages with many tabs each. Every once in a while, pages will not correctly respond to being clicked on. The page comes to the front, but Safari does not show as the front-most application. I cannot select and activate it via the Dock or by command-shift-tabbing. Movies may continue to play in a page, so it's not frozen, by any means.
Also, ActivityMonitor does NOT show it as locked up or frozen, nor is it consuming crazy amounts of RAM or CPU cycles. There is free RAM available.
Anyone have any ideas?
MBP 17 2.4 ghz 4 gig, Mac OS X (10.5.4), Pretty stock, swapped HD to a 320