I've been having some trouble getting help for this problem in the IRC channels, so here goes.
Nothing responds when I click on anything in flash elements. ( The sole exception being the music player at Playlist.com, which might not even be flash-based. ) Buttons do glow properly when you hover over them, though.
I'm running Firefox 3.5.4 on 32 bit Fedora 12 that I upgraded from F11. All of my packages are up to date, and I'm getting the Flash plugin from the Adobe repo. It's version 10.0.32.18.
This wasn't happening before I upgraded.