This is something we've been discussing internally for some time now.
Things to note:
- dart-sass's precision is hardcoded to 10; I dropped it down to 6 for the minified files, but we might want to reconsider this and just go with the default? I need to check how much it adds, though
- dart-sass orders grouped selectors differently; I have not found a way to work around this and perhaps we should ask upstream. Do note that the minified files keep the old behavior since clean-css sorts the grouped selectors alphabetically
- dart-sass converts escaped UTF-8 characters which in turn means we need a
@charset "UTF-8";. Not the end of the world, but it is something to note. Also, note that there's a--no-charsetflag, but then this could be dangerous since we do have Unicode characters, so we better not use it - dart-sass removes quotes from attribute selectors; not a big deal since they are already removed in the minified files
- dart-sass adds leading zeros; again, not a big deal since they are already removed in the minified files
- other minor output differences like whitespaces
@twbs/css-review for discussion
- Check the bundlewatch size differences
- Live preview: https://deploy-preview-31728--twbs-bootstrap.netlify.app/
- Test that sourcemaps work properly; I see some changes in soucemaps'
sourcesproperty
Refs #29853