Add scrollbar-{auto,thin,none} utilities for scrollbar-width, and scrollbar-thumb-* / scrollbar-track-* color utilities for scrollbar-color (#19981, #20019)
Allow using @variant with stacked variants (e.g. @variant hover:focus { … }) (#19996)
Allow using @variant with compound variants (e.g. @variant hover, focus { … }) (#19996)
Support --default(…) in --value(…) and --modifier(…) for functional @utility definitions (#19989)
Fixed
Ensure @plugin resolves package JavaScript entries instead of browser CSS entries when using @tailwindcss/vite (#19949)
Fix relative @import and @plugin paths resolving from the wrong directory when using @tailwindcss/vite (#19965)
Ensure CSS files containing @variant are processed by @tailwindcss/vite (#19966)
Resolve imports relative to base when result.opts.from is not provided when using @tailwindcss/postcss (#19980)
Canonicalization: preserve significant _ whitespace in arbitrary values (#19986)
Canonicalization: add parentheses when removing whitespace from arbitrary values would hurt readability (e.g. w-[calc(100%---spacing(60))] → w-[calc(100%-(--spacing(60)))]) (#19986)
Canonicalization: preserve the original unit in arbitrary values instead of normalizing to base units (e.g. -mt-[20in] → mt-[-20in], not mt-[-1920px]) (#19988)
Canonicalization: migrate arbitrary :has() variants from [&:has(…)] to has-[…] (#19991)