Why we have nesting of where in dl ol ul ? ( :where(dl, ol, ul))

Why do we have a double nesting of where for dl,ol,ul ?

:where(dl, ol, ul) :where(dl, ol, ul) {
margin-block-end: 0;
margin-block-start: 0;
}

Actualy that's not working for only 1 nesting like :

Coffee

Black hot drink

https://github.com/csstools/normalize.css/blame/a4a0c202e8b34426e0cd8e0411005906cd94e407/normalize.css#L36

Start by reading the selector in normalize.css around the linked line and compare its behavior with the single-nesting

example in the issue. Determine whether the reported behavior is intentional or a selector defect; done means the rule's purpose and the expected behavior are clear, with the stylesheet updated if needed.

Written by the indexing model from the issue text.