astro/.changeset/friendly-fishes-sing.md

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'astro': minor
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Implement Inline Stylesheets RFC as experimental
feature: configuration for css inlining behavior (#6659) * feature(inline stylesheets): implement as experimental * test: rename css-inline -> css-import-as-inline * test(content collections): add de-duplication of css * test: add new suite for inlineStylesheets configuration * fix(inline stylesheets): did not act on propagated styles * hack(inline stylesheets testing): duplicate fixtures Content collections reuses build data across multiple fixture.builds, even though a configuration change may have changed it. Duplicating fixtures avoids usage of the stale cache. https://cdn.discordapp.com/attachments/1039830843440504872/1097795182340092024/Screenshot_87_colored.png * refactor(css plugin): reduce nesting * optimization(css rendering): merge <style> tags Chrome, but not Safari or Firefox, is slower to match rules when they are split across multiple files or style tags. https://nolanlawson.com/2022/06/22/style-scoping-versus-shadow-dom-which-is-fastest/ Having the abiility to inline stylesheets opens us up to this optimization. Ideally, it would extend to propagated styles, but that ended up being a rabbit hole. * typedocs(inlineStylesheets config): ensure consistency Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca> * chore(build internals): update comment * correct minor mistake in test * test(inline stylesheets): unique package names for duplicate fixtures * refactor(css build plugin): maps -> records * refactor(css build plugin): remove use of spread operator --------- Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca> 2023-05-03 18:49:06 +00:00			`---`
			`'astro': minor`
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			`Implement Inline Stylesheets RFC as experimental`