Mozilla/5.0 (X11; Linux x86_64; rv:12.0a1) Gecko/20120125 Firefox/12.0a1 This was found when looking over bug 701251. 1) Visit http://blog.pearce.org.nz/2011/11/firefoxs-html-full-screen-api-enabled.html 2) Control-F or Command-F to bring up the find bar at the bottom of the browser. 3) Click the page's "Make video full-screen" button (below the video) 4) Exit full screen Actual result: find bar isn't active anymore.