Missing -background-variant-color

[trixon]

I tried to set -background-variant-color in my css in order to change the background color of pressed module toolbar items but it had now effect.

For a light theme one can see the hard coded default mask in _content-view.scss

        &:pressed {
          -fx-background-color: rgba(0, 0, 0, .075);
        }

but it's invisible in a dark theme.
I added the following to my css and it works as expected

.toolbar-button:pressed{
    -fx-background-color: red;
}

I'm still a beginner of css but doesn't it make sense to expose -background-variant-color, similar to the -primary-variant-color?