#Applescript file to control #play / #pause #priority when run. Priority here is: If Quicktime has focus, play/pause in qt; if VLC has focus, play/pause in VLC; otherwise play/pause in Spotify

CustomPlayPause.scpt

on run {input, parameters}
    
	tell application "System Events"
		set MyList to (name of every process)
	end tell
	
	set nameOfFocusedApp to name of (info for (path to frontmost application))
	
	if (MyList contains "QuickTime Player" and nameOfFocusedApp is "QuickTime Player.app") is true then
		tell application "QuickTime Player"
			tell document 1 to if exists then
				if playing then
					pause
				else
					play
				end if
			end if
		end tell
	else if (MyList contains "VLC" and nameOfFocusedApp is "VLC") is true then
		tell application "VLC" to play
	else if (MyList contains "Spotify") is true then
		tell application "Spotify" to playpause
	end if
	
	return input
end run