Recast time in hotbar keys

[Knoxay]

I don't know if anyone else would find this useful, but I think it would be nice if the recast timer for spells could be displayed over hotkeys. I use my keyboard to cast so it's not worth hovering over for, and the gray "hour glass" timer isn't very precise (especially with 3/4 size hotkeys).

Is this possible? Maybe it's been done and I missed it.

Thanks