If you have a spoofed version set in about:config, AUC alternates between your current version and spoofed version on the timer. So if you entered 7 and are running 10 it will check 10, 7, 10, 7... The icon is now not set until update checking is complete. Before, the icon could get set, but the tooltip wouldn't show up until checking was done and if there was a network error it may never show up. The door hanger notification now uses the AUC icons and can be re-shown by clicking the icon and is not removed by clicking on 'Not Now', the 'X' or page content. Added a menu entry to door hanger to hide this notification since you can only have one notification shown at a time. Door hangers hide automatically when you change tabs or locations. Door hangers don't work well with the option to show the 'Available Updates' page since the url bar is hidden on that page and that's where the notification anchor is. Disabled the door hanger option in the options page for Thunderbird. Thunderbird has the popup notification module, but it does not seem to work even when installing add-ons etc. If it gets support, I'll enable it. Hopefully fixed default right-click menu showing when it should not have done so.