Opaque parts of any element.

A feature request: A part of any item (such as slur, hairpin, beam, staff lines) should have ability to become opaque.
This can be achieved by selecting two items, and which would be assigned as foreground and background. All other elements would remain intact.

By choosing opaque background (and size of it) for the foreground item, the background item should be "removed".

In this example, the beam is assigned to "background", the small brace + ledger lines + noteheads are assigned to "foreground".

This would be very useful for example for slurs when colliding with accidentals (a huge vertical space saver).