# Astro astro@6.0.5 — Release & Upgrade Intelligence
- **Product:** Astro (https://astro.build)
- **Version:** astro@6.0.5
- **Released:** Mar 16, 2026
- **Impact Score:** 5/10
- **Breaking Changes:** Not verified
- **Canonical Analysis:** https://changelogs.us/astro/updates/astro-6.0.5/

## Executive Summary (TL;DR)
Astro astro@6.0.5. Source highlight: Fix dev routing for `server:defer` islands when adapters opt into handling prerendered routes in Astro core. Server island requests are now treated as prerender-handler eligible so prerendered pages using `prerenderEnvironment: 'node'` can load island content without `400` errors.

## Bug Fixes
- Fix dev routing for `server:defer` islands when adapters opt into handling prerendered routes in Astro core. Server island requests are now treated as prerender-handler eligible so prerendered pages using `prerenderEnvironment: 'node'` can load island content without `400` errors.
- Fixes `astro:actions` validation to check resolved routes, so projects using default static output with at least one `prerender = false` page or endpoint no longer fail during startup.
- Avoid a `MaxListenersExceededWarning` during `astro dev` startup by increasing the shared Vite watcher listener limit when attaching content server listeners.
- Emit the `before-hydration` script chunk for the `client` Vite environment. The chunk was only emitted for `prerender` and `ssr` environments, causing a 404 when browsers tried to load it. This broke hydration for any integration using `injectScript('before-hydration', ...)`, including Lit SSR.
- Fixes an issue where `<style>` tags inside SVG components weren't correctly tracked when enabling CSP.
- Ensure custom prerenderers are always torn down during build, even when `getStaticPaths()` throws.

## Upgrade Command
```bash
npm install --save-exact astro@6.0.5
```