Idea for "rage quit"

I just had a tourney game where my opponent did a rage quit.
Even though there was the green sign for my opponent (instead of the open door, red/brown sign), I got the "claim win", "call draw" option with some 1 minute 50 sec. to go.
A few months ago I was thinking to myself that rage quit in a tourney game could be answered by waiting the time out.
My opponent does a rage quit but one could answer it with sitting it out which would prevent myself *and* my opponent to continue the tourney.
Of course one could choose to quickly win or draw, but how about a 3rd button with "play some random music while waiting", like the Free Software song by RMS, or Tom Waits "The piano has been drinking", Charlie Parker, Simon & Garfunkel live in Central Park etc. :)

Besides this I am very curious why I sometimes get the "claim win"/"call draw" very fast, and sometimes very late.
How is that technically detected and act upon ?
And in this case today, why did I still see the green sign from my opponent and still got the "claim win" option ?
Is it because they moved to another browser tab instead of closing it ?

I wonder the same thing. Sometimes it comes within 10 seconds and I did not know it was suppose to come that quick. Today I was playing as anonymous and it came instantly (2 or 3 seconds) after he made a move that hung mate in 2 also the move was hanging a rook.