Installed and running addons:
ShestakUI, ShestakUI_Config, Bugsack, Buggrabber
Screenshot(if that matters for error):
Lua error code(if that matters for error):
How to reproduce error:
Just get full CCed in a battleground and the cooldown number can disappear and will reappear when you press a button while in a full CC. Once you come out of it, they seem to work normal again.
Just to mention. I was running through a Lib called LibActionButton-1.0. It has some really good ways to handle charges and such for cooldowns. I am not sure if this will return useful though.