Please give us an extra setting's option "as in layer xy" (reference instead of copy)

For e.g. white balance, layer mask, ...

Doesn't mean to copy, but to _reference_ the setting; means: if changed on referenced (defining) layer, it will change on referencing layers as well.

For masks, I'd appreciate being able to reference to another layer and add a switch like "inverted" (for: some mask / all remaining).

Referencing variants would be convenient to keep different crops "up to date".