User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Fedora/1.0.4-1.3.1 Firefox/1.0.4 Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.8) Gecko/20050513 Fedora/1.0.4-1.3.1 Firefox/1.0.4 If you follow a link on a page that points to a URL that is identical to the current page except for case differences, it is impossible to use the back button to return to the page you were on. It seems that Firefox seems to treat such a link as a reload of the current page instead of a different URL. Remember, only the "http://server/" part of a URL is case-insensitive; the path is allowed to be case-sensitive (and often is). Reproducible: Always Steps to Reproduce: 1. Go to http://en.wikipedia.org/wiki/Avi 2. Click on the link at the top ("For the file format, see AVI.") which goes to http://en.wikipedia.org/wiki/AVI Actual Results: If the "Avi" page was the first page loaded in a tab, the back button is disabled. Otherwise, the back button will take you to the page before "Avi". Expected Results: From "AVI", the back button should return you to "Avi".

*** This bug has been marked as a duplicate of 99091 ***