Exiting Fullscreen with the Esc key only works once

Every time the first stream I watch is fullscreened then closed with the esc key, I can't close the fullscreen with the esc key again if I wanted to watch any stream in fullscreen. I would have to instead close it by clicking the Fullscreen button with my mouse pointer. When I make a new Twitch tab/window in my browser, the problem persists. When I end my browser's process and open it up again to a Twitch stream, the esc key to close fullscreen only works once until the next time I close my browser. No problem on Windows 7 (same computer). My OS is Ubuntu 13.10, browser is Chromium version 30.0.1599.114, Flash version 30.0.1599.114.