[Feature Request] Simple Actionbar Background

[AngelosNaoumis]

Is your feature request related to a problem? Please describe.
My request is not related to a problem but a feature request in order to simplify my UI.

Describe the solution you'd like
I would like an option change to simply dark the background of actionbars.

Describe alternatives you've considered

1. Change the texture directly in Addon Folder
2. Bartender with Masque (for borders)

Additional context

[AngelosNaoumis]

I only have an empty texture so I do it like that

[AngelosNaoumis]

Blizz UI has also the option just for reference