is there a way to disable tab scrolling in firefox 4? So that i am able to view all tabs at any time (like in opera oder chromium/chrome). As far as i see the only posibilty comes with extensions like tab mix plus, that are not avaible for ff4.
I would suggest checking about:config. There should be a browser.tabs.tabMinWidth option, or similar. Setting that to zero will allow the tabs to keep getting squished without falling back to tab scrolling.
Having actually gone and installed Firefox 4 beta 10, it seems that's been removed. I searched around a little, and what finally worked was a userChrome.css modification.
Add to, or create userChrome.css in the chrome folder in your profile, and paste these lines in it:
16 pixels is the width of the icon, thus tabs will never actually disappear, but you should be able to open many more tabs before scrolling kicks in.