dom-css-inliner

It appears, AFAIK, currently no CSS inlining library supports modern selectors like :has(). So this is a (largely vibe-coded) new CSS inliner that employs DOM and CSSOM APIs to support them.

Specificity is meticulously simulated and tested with a test suite.

Inheritance control (inherit, revert) is NOT supported.

I wanted to add pseudo-element inlining as well, but without a Window this can become quite complicated so I dropped the idea.

I don't know yet whether shorthand properties and nested rules are rigorously handled.

Usage

import { inlineCss } from "@the_dissidents/dom-css-inliner";

inlineCss(myDocument, {
    removeStyleTags: true,
    removeClasses: true
});