Biome 2.5.10

Biome CLI 2.5.10 was released on August 21, 2026. This patch focuses almost entirely on correcting Astro parsing behavior, addressing several long-standing issues where valid Astro markup was being rejected or mis-formatted. No new public APIs were introduced; this is a stabilisation and correctness release.

Overview

Release 2.5.10 (August 21, 2026) resolves a cluster of Astro parser defects reported against earlier 2.5.x builds. The changes are targeted at the Astro source language and improve the fidelity of formatting and analysis for real-world Astro components.

New Features

There are no new features in this release. All user-facing changes are bug fixes.

Bug Fixes

• JavaScript comments between Astro attributes — Biome no longer rejects comments placed between attributes, such as <div /* block comment */ class="something"></div>.
• Bare < in Astro text — a lone less-than sign that cannot open a tag is now treated as text, matching HTML behavior (e.g. <p>5 < 6 and 7 > 6</p>).
• Comment-only expressions — an Astro expression holding only a comment (e.g. <div>{/* a note */}</div>) is no longer reported as a parse error, and the file is formatted correctly.
• Empty expressions — <div>{ }</div> no longer fails to parse; an empty expression renders as nothing per Astro semantics.

Deprecations

None in this release.

Fixes in Detail and Credits

The primary patches originate from PR #11403 and PR #11438, contributed by Oxygen (Princesseuh). Contributions also address GitHub issues #8294, #9165, and related parser concerns. The team thanks all contributors for the continued improvement of Astro support.