I'm trying to create a meta icon that will flash cooldowns as they become available and then disappear.

For example:

I have dark soul and an on use trinket in an 'always hidden' group. I want the meta icon to flash for a second or so when the ability becomes available and then disappear and not not show up again until the cooldown because available again. All I can figure out now is the icon appears when the spell is available and won't hide until I use the spell.