I tried Firefox 3 beta 4 just now, and there were a few bugs that stood out in the first few minutes:
12305 Firefox 3 beta 4 font problem: colon displayed as 0038 unicode glyph-missing glyph 12306 Firefox 3 beta shows one-pixel-high black line when rendering some images 12307 firefox 3 beta 4 crash on some web pages
Youtube seemed slow and hangy on the first video I tried, http://www.youtube.com/watch?v=jwMj3PJDxuo although it was fine in native firefox at the same time; perhaps the Windows version of the flash plugin is less resistant to network errors -- or Wine doesn't support some network feature that only matters during bad internet weather.
That same video was fine later, as was a different video http://www.youtube.com/watch?v=OGxdgNJ_lZM (both worth watching, btw).
It also output quite a few messages like fixme:ntdll:NtLockFile I/O completion on lock not implemented yet fixme:font:ExtTextOutW flags ETO_NUMERICSLOCAL | ETO_NUMERICSLATIN | ETO_PDY unimplemented
Firefox 3 rc1 will be out in May, and release will be in early June, according to http://blog.wired.com/monkeybites/2008/03/mozilla-final-v.html
Given that a lot of people have in the past used windows Firefox in wine to run native plugins, maybe we should get firefox 3 working well. Probably only five or six main issues. - Dan