That's the shortcut I use for bookmarking, get off my lawn.

Skype for business uses Win-F4 to mute. No kidding.

Pro tip: alt+f4 also mutes... ;)

Right, that's my point. Which makes me think this is really a sick joke by some disgruntled engineer.

Out of all of the 48 major keys each with 16 possible modifier key combinations, how on earth did they settle on the one keystroke within a thumbnail of closing the application.

It's not just rude. It's an F-you to the user.

Wish some hotkeys like m or f in youtube would be universal.