Have you tried zooming /questions/847465 or scrolling.

If you continue to have problems more information would help. Please answer in the current (or your own) thread:

• What display resolution are you using ?
• Exactly what is lost, and sides or top ?
• What does it affect, does it occur with blank pages, or only certain websites
• Maybe you could add a screenshot from
  • firefox 4
  • and firefox 5 so everyone can see what is happening.
• (asked originally in thread /questions/847840 )

I tried that. Does not solve the problem. The entire site layout is way off. everything is on the left side now. And it is all just a list of text. And any graphics have disappeared too. When I open this website with Explorer, it looks like it should. This problem only began last night with Firefox. What can I do to fix it? Does anyone know?

Clear the cache and the cookies from sites that cause problems.

"Clear the Cache":

• Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"

"Remove Cookies" from sites causing problems:

• Tools > Options > Privacy > Cookies: "Show Cookies"

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.
• https://support.mozilla.com/kb/Safe+Mode

• https://support.mozilla.com/kb/Troubleshooting+extensions+and+themes

Thanks cor-el! This solved the problem perfectly.

Note some similar problems are being caused by the Babylon Toolbar, it may be worth considering disabling that if it is installed.

If all content is placed at the left side then that sounds like corrupted or missing CSS files and clearing the cache can help in such a case. Extensions like Adblock Plus also can block CSS files and cause this issue.
The Babylon issue causes a too width page without scroll bars and that is something different.