Bug: Pause when window loses focus does nothing(?)

[Mr Weedy]

It seems the "pause when window loses focus" setting does nothing. The music still keeps playing on the background and it feels like the game is still running on the background as usual when you click out of it.

I'm running the game in Fullscreen Borderless so you would assume the game knows when the window isn't activated and another window is activated instead. Could you take a look into this and why the music isn't pausing when the game loses focus?