Feature Request: Notification when opponent leaves the game when I'm in another tab

[dryguy]

Currently, if I am in another tab when my opponent moves, I get a notification from the browser that it is now my move, which is nice.

I would like to request a similar notification when I am in another tab and my opponent leaves the game. The reason is that when an opponent decides to "rage-sit" and run out their clock in a lost position, I will generally switch to browsing the internet while I wait for their clock to run out. Sometimes, I will return to find that they actually left the game some time ago, and I could have claimed my win and moved on to another game instead of killing time on reddit.

Preferably, the notification wouldn't occur as soon as they leave the game. Instead, I would be notified as soon as I was allowed to claim victory.