When I attempt to shut down my computer with Firefox running, it doesn't close like it should during the shutdown. Instead, it hangs (as described in [[Firefox hangs|this article]]), and will continue to do so until I stop the shutdown process and close it manually, where it will still not be responding. There's the basic issue. Here's the list of relevant data to pin it down more precisely: On the list of programs still active during the shutdown, the Firefox window starts out only appearing once like it should, but a few seconds after starting to hang it starts to appear a second time on the bottom of the list, with the specific name of the page being a duplicate of whatever it is on the original one. This problem does not occur in safemode, but it's not caused by any of my addons either, as I figured out after disabling all of my addons through Tools>Add-ons rather than through safemode and still having the problem. It's listed as happening a few times a week, but that's just because that's how often I forget to close Firefox before pressing "shut down" and leaving the room without bothering to check that it's working. It happens every single time I attempt to shut down the computer with Firefox running though.