Just had an update to Firefox 3.6.13. Since the update, I have a bizzare problem. Every time a page loads, the circulating progress icon in the tab freezes until I move my mouse pointer, and then the page loads. Also, if I open the Help window (Help / About Mozilla Firefox), then if I don't move my mouse after clicking in the menu, the help box does not appear until I do move my mouse. I have left the browser several minutes in this state which always recovers when the mouse pointer is moved. Doesn't happen if the loaded page is cached (using < and > ). This did not happen on any other previous version.