Update: always check '''every''' addon, even when they don't change the UI. Facebook Disconnect messed up my UI for no reason. After upgrading Firefox automatically to version 10.0 the top UI area (menu button, tabs, address bar, etc.) has been acting strange. * I need to toggle a few different settings for the menu button to settle properly. Otherwise the Firefox icon and current tab title is visible on a single line on the top (not wanted) with the menu button under it on a line of its own. * The current tab URL doesn't update to the address bar properly (same URL visible on all tabs). * Bookmarks toolbar is randomly disappearing. * Randomly not loading a page after typing an URL to the address bar and hitting Enter. As I said if I toggle a few tool bars or click random buttons they settle to correct positions. The address bar issue is still quite irritating. The only visible addon UI elements are Web Developer Toolbar, AdBlock Plus button, Firebug button and Ghostery button. Otherwise everything is the vanilla UI (except a few repositioned navigation buttons). Is this happening to anyone else or should I try something special?