SCSS becomes much more complete
SCSS parser/formatter support expanded across core syntax — Biome added support for @include ... using, parent selectors, semicolonless statement at-rules, interpolated attribute selectors, interpolated dashed identifiers/properties, keyframes selectors, and raw string interpolation. These changes also wired through new syntax nodes, factories, generated types, and formatter paths so Sass-heavy code should parse and print far more faithfully.
CSS/SCSS analysis got more accurate — Interpolated SCSS pseudo selectors are now recognized instead of flagged too early, and plain CSS custom functions are distinguished from Sass @function declarations. That reduces false positives and closes several parser/linter gaps between CSS and SCSS syntax.
Markdown parsing was tightened in several edge cases
List and block container handling improved — Multiple fixes landed for tab-indented lists, sibling markers, ordered sublist continuation, and list continuation after quote prefixes. Together they make CommonMark-style nested lists and blockquotes behave more reliably and reduce parser/serializer drift.
YAML formatting is starting to take shape
Experimental YAML formatter plumbing landed — Biome now has YAML-specific config wiring, service/file-handler integration, and formatter test coverage. The formatter remains disabled by default, but the groundwork for first-class YAML formatting is now in place.
Other notable changes
Tailwind and Svelte parsing got sharper — Tailwind arbitrary values now distinguish numbers from percentages, useSortedClasses got scaffolding for Tailwind v4 presets, and Svelte function bindings are parsed more precisely to avoid incorrect diagnostics.
Linting and diagnostics improved — useDestructuring now mirrors ESLint’s configurable contexts, noUnusedFunctionParameters reports the actual parameter name, and biome rage --linter now includes domain-enabled rules in its output.
HTML and tooling fixes — HTML formatting no longer produces invalid output when comments split tags, React Native deep-import migration source mapping was corrected, and the repo also saw benchmark removal plus assorted dependency, CI, and docs cleanup.