ElementRef doesn't support basic shapes.

[lemmih]

See https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/clip-path#Usage_notes and https://developer.mozilla.org/en-US/docs/Web/CSS/basic-shape

This is a low priority issue for me.

[Twinside]

This is not an SVG feature, it's a CSS one that doesn't look finalized (CSS Shapes)