i use firefox4 beta and didnt had problems with it.
i use it as allways sandboxed /partially limited.
24 hrs ago i updated to ff 4 beta 8, whenever i use it and sandbox is on i get a bsod when i close the browser.
i tried a clean install of this beta version,i cleaned previous files from the virtualroot and nothing helps.
i checked the bsod dumps and it allways the sandbox driver that comes up.
i dont get bsod when the sandbox is disabled,and when enabled only ff4 b8 causes this bsod and only when i close it.
UPDATE: after turning off registry and file system virtualization from the advanced edit menu for firefox i dont get bsod after closing the browser.
i suspect this has to do with the hardware acceleration introduced to ff in this beta version, is there a way around it? i allready posted a bug to firefox.