Map Cooldown Fix fixes the bug in the default UI where spell cooldowns are hidden upon closing the world map. Map Cooldown Fix forces each action button of the default UI to update its cooldown whenever the map closes, which forces the cooldown timer to be redisplayed.
Please let me know if you have any issues.
Update: Yet another one of my addons appears to be unnecessary. I finally managed to get around to testing the issue this addon fixed without the addon installed after 6.1's release, and it turns out I no longer see this issue. As such, I'm assuming Blizzard fixed the problem, and I am marking this addon as obsolete.
