WebKit has started implemented some Geometry interfaces (https://bugs.webkit.org/show_bug.cgi?id=133916, https://bugs.webkit.org/show_bug.cgi?id=163464).
The Geometry interfaces spec (https://drafts.fxtf.org/geometry/) has gone through some changes recently (https://drafts.fxtf.org/geometry/#changes).
This include structured cloning as well as new constructors to *ReadOnly interfaces.
To achieve conformance with other browsers like Chrome, it would be better to update these implementation to match the latest spec.
I implemented DOMPoint and DOMRect to the latest spec, but then added the v1 DOMPoint constructor IIRC. That change could be rolled out.