Subtract / mask shapes

[PiewieP]

Feature Description

I'd like to cutout / mask / subtract one shape from another, so I tried out groups; opacity and shape order in several configurations but to no avail. Would this be possible at the moment?
Image below for reference, the center white circle should be transparent. Closest I got so far is to make the center white.

[MewPurPur]

Masking is a feature in SVG, but for now this has to be done through the code editor. This feature is blocked by the pending inspector rework, which I should start working on again after alpha 15.

Edit: I settled on a smaller alpha 16 without inspector rework stuff, for personal reasons I want to get something out quickly right now.