[`shape-outside`](https://drafts.csswg.org/css-shapes-1/#shape-outside-property) (CSS Shapes 1) and [`shape-inside`](https://drafts.csswg.org/css-shapes-2/#shape-inside-property) (CSS Shapes 2) are defined with this prose: > **`<basic-shape>`:** The shape is computed based on the values of one of `inset()`, `circle()`, `ellipse()` or `polygon()`. It is not clear to me if `xywh()`, `rect()`, `path()`, should be invalid. In SVG 2, `<basic-shape>` is even further restricted in [`shape-inside`](https://svgwg.org/svg2-draft/text.html#TextShapeInside) and [`shape-substract`](https://svgwg.org/svg2-draft/text.html#TextShapeSubtract), but I assume these are superseded by CSS Shapes. <sup>This was previously reported in the multi-faceted issue <a href="https://github.com/w3c/csswg-drafts/issues/7390">#7390</a>.</sup>