User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:40.0) Gecko/20100101 Firefox/40.0 Build ID: 20150730171029 Steps to reproduce: Whenever I close an active tab or create a new one, not interacting with the firefox window any further and then toggle windows' notification window on and off, it will switch the active desktop. Somehow activation/focus seems go crazy there. Actual results: Active Desktop switched Expected results: Active Desktop shouldn't switch and focus should go back to the last Firefox-Window

(In reply to firefox from comment #0) Please note: Bug was issued by a user on IRC #firefox Please do NOT ask me about more details as I don't have any.

I'm not sure what problem comment 0 is describing. Something with the Win10 virtual desktops? I gave it a quick test but don't see anything obviously wrong? Further details would be helpful to make this actionable.