I have installed flashplayer plugin 9 beta 2 from labs.adobe.com site and it looks that this bug in flashplayer has been fixed there. Firefox works without problems now in 16bit depth and without XLIB_SKIP_ARGB_VISUALS setting. Now we need to get this packaged for ubuntu.
-- Flash plugin problem with ARGB visuals causes crash https://launchpad.net/bugs/14911 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs