whiteout-color property
In fancy situations like #6030 (closed), one might want to change the color of the whiteout created when a grob has its whiteout
property set, or when using \whiteout
in markups.
The functions defined in scm/stencil.scm for producing whiteout accept a color argument, so it's possible to do this in Scheme, manipulating the stencil. It seems we just need properties to interface with this parameter.