User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.84 Safari/537.36 Steps to reproduce: I selected Firefox 58 even though I am on Nightly 59.0a1 because when I go to your wiki and click "How do I report a bug" it links to this Bugzilla instance, which only goes up to 58. So you'll need to triage this bug, and also maybe make it easier for users to figure out how to do it right in the first place. That said, Firefox Nightly is restarting onto the wrong virtual desktop on OS X High Sierra. Actual results: When I click "restart to update," the update installs, then Firefox makes my virtual desktops wiggle back and forth three or four times (very annoying and distracting) and then it starts on a different virtual desktop than the one it was on. I then have to drag the window over to the right desktop. Expected results: This shouldn't happen. If I wanted the window on a different desktop I would have put it there. And don't be like "oh this is an OS X problem, you should go to Apple" because it doesn't happen in Chrome or Safari. I know you know how window management works on OS X.