Comment 29 for bug 213528

Backed up all important stuff and did a fresh install of Ubuntu from a new download.
After finally rebuilding all the apps etc, recovered from data backup.
Configured Firefox the way I prefer it, made sure bookmarks worked correctly.
Imported the entire set of bookmarks from HTML file, noticed that some of the default bookmarks were duplicated so cleaned that up.
Restarted Firefox and now have bookmarks working correctly.

Assumption is that _something_ left around when upgrading from 7.10 to 8.04 was at the root of the chaos.

Firefox 3 still isn't particularly stable but that's a separate issue.