User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9b1) Gecko/2007110904 Firefox/3.0b1 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9b1) Gecko/2007110904 Firefox/3.0b1 When Firefox 3 is first started it imports addons from default profile. It checks for compatibility for the addons and themes. Now if a proxy is configured and proxy required authentication then firefox will ask for username and password for each addon/theme. Although this will happen only once but its very annoying to enter the same username & password 10 times (or more, depending on addons/themes installed). Reproducible: Always Steps to Reproduce: 1. Ensure Firefox 2 has some addons/themes 2. Ensure that Firefox 2 has a proxy configured that required authentication 2. Install Firefox 3 beta 1 3. Start Firefox 3 beta 1 Actual Results: foreach in (addons + themes) I was asked for username and password for proxy authentication done Expected Results: It did check for compatibility Software should have asked for username & password only once and either cached it for the session where addons/themes compatibility is checked or an option to remember the password should have been given to remember the username/password for proxy.