Where can I see in tooltips that overpower reduce mortal cd?

[hasnogaems]

Because it is. But I cannot find mention about it in any tooltip.

[Neff]

In patch notes: https://wow.gamepedia.com/Overpower

Mists of Pandaria Patch 5.2.0 (2013-03-05): Now costs 10 rage and reduces [Mortal Strike]'s remaining cooldown by 0.5 seconds.