WotLK Clean Plates (Tidy Plates) not showing caster bars under the name plates.

[Aesis6]

I thought that Tidy Plates was supposed to show the caster bar under the name plate but it does not do it unless I specifically target the caster for some reason.

Here is an example: https://imgur.com/a/As3H7BZ

How can I get it to work without having to target them?

Yes, I checked Cast Bars on Nameplates in the Combat menu.

[OhieMitzen]

I don't think you can. Not that I'm aware of.