Pin/lock any item color in a theme

There are colors that I like to use for certain things but have to redo them each time I want to try or use a new theme.

It would be nice to be able to pin or lock any item color so it is ignored when testing/trying out themes one after the other. Not a complete hassle to adjust these things once settled on a theme, but would be 20-30 less clicks to get the colors back to what I want.

Maybe right-click the color and select "Lock" or "Pin" or "Freeze" or something. Then show a lock next to the color for easily spotting them.