The headline feature is that R3F is now compatible with React 19.3.0. We don't fully support all of the new APIs, but it will not longer conflict to run the latest and greatest React.

In addition we fixed some long standing bugs:

• React roots are configured synchronously and then gated on the renderer if it need async, for example with WebGPURenderer. This means that you won't get awkward out of sync issues.
• Strict Mode no longer causes problems for our canvas. This was related to the async support added a while ago as well.

Have fun!

• fix: corrected broken links by @dor-rondel in https://github.com/pmndrs/react-three-fiber/pull/3872
• feat: support React 19.3 by @cades in https://github.com/pmndrs/react-three-fiber/pull/3916
• fix(core): don't tear down a root remounted during the unmount grace period by @abernier in https://github.com/pmndrs/react-three-fiber/pull/3869
• feat(core): configure and render roots synchronously by @krispya in https://github.com/pmndrs/react-three-fiber/pull/3925

• @dor-rondel made their first contribution in https://github.com/pmndrs/react-three-fiber/pull/3872
• @cades made their first contribution in https://github.com/pmndrs/react-three-fiber/pull/3916

Full Changelog: https://github.com/pmndrs/react-three-fiber/compare/v9.7.0...v9.8.0

• #18063 40896ac Thanks @adamchal! - Fixes incremental builds repeatedly rendering unchanged pages when modules or compiled CSS reference bundled assets.

• #18053 cf5d72f Thanks @Princesseuh! - Improves the astro check error shown for TypeScript 7. The command now explains that TypeScript 7 is not currently supported and provides instructions for experimentally type-checking Astro files with TypeScript 7.1 and @astrojs/ts-content-mapper.

• #18086 795a7e4 Thanks @ump45nose! - Fix double-escaped ampersands in Markdown image alt and title attributes. The __ASTRO_IMAGE_ round-trip now decodes the numeric (&) and named (&) character references the Markdown processors emit, so an & in an alt or title is escaped exactly once in the final HTML instead of twice.

• #18074 0429805 Thanks @SurefireStudios! - Fix three error names that did not match their documented reference. MissingLocale, MissingIndexForInternationalization and NoManifestAvailable reported names ending in Error in the dev overlay, while their error reference pages are published under the unsuffixed names, so the name shown to users could not be found in the docs.

• #18007 2245837 Thanks @L4XB! - Fixes the dev server re-evaluating the whole server module graph on every request. The astro:head-metadata plugin invalidated its component metadata virtual module from its own transform hook, so each evaluation of that module scheduled the next one. Adapters that run requests outside Vite's module runner, such as @astrojs/cloudflare, paid for a full re-evaluation of the server graph on every request for the lifetime of the process.

• #18096 43657c4 Thanks @matthewp! - Fixes domain-based i18n routing to respect security.allowedDomains when selecting a locale from request host headers

• #18043 8a53a8b Thanks @astro-factory! - Fixes image.responsiveStyles emitting invalid object-position CSS values for same-axis keyword pairs (top bottom, left right, etc.)

• #18029 c08252d Thanks @matthewp! - Runs astro dev and astro preview in the foreground when an AI agent is detected on Windows, allowing the agent to manage the process lifetime. Pass --background explicitly to request an Astro-managed background process. Agent-inferred backgrounding remains enabled on other platforms.

• Updated dependencies [3fd16ee, 8358d59]:

  • @astrojs/markdown-satteri@0.4.2

• #18059 30cb32e Thanks @Princesseuh! - Fixes image transforms without a specified quality outputting an higher quality than expected on certain formats

• #18091 28d59a9 Thanks @astro-factory! - Fixes optimizeDeps.include glob astro/runtime/** matching .d.ts files, which caused 83 unnecessary optimizer entries and empty output chunks per environment during dev

• #18032 f7dbc6a Thanks @adamchal! - Fixes image requests when using imageService: 'compile' with passthroughImageService().

• Updated dependencies []:

  • @astrojs/underscore-redirects@1.0.4

• #17986 b1f9088 Thanks @hanford! - Updates @qwik.dev/partytown from 0.13.2 to 0.14.4, bringing fixes for analytics event forwarding and iframe loading, support for Google Tag Manager's Tag Assistant preview, and automatic execution of scripts added after client-side navigation.

• #18050 cea7da5 Thanks @Princesseuh! - Adds the initial release of the TypeScript content mapper for Astro files.

• #17951 e5b0ac4 Thanks @hanford! - Migrates the React integration to @vitejs/plugin-react v6, using Oxc for JSX and Fast Refresh. Removes the babel integration option; projects with custom Babel transforms must configure @rolldown/plugin-babel under vite.plugins instead.

  Adds an opt-in compiler option for the Oxc-based React Compiler. Install oxc-transform-react and enable it in your Astro config:

  import react from '@astrojs/react';
  
  export default {
    integrations: [react({ compiler: true })],
  };

  The compiler memoizes client components and hooks. Server rendering is not compiled. The target defaults to the installed React major version; React 17 and 18 projects also need react-compiler-runtime installed. Pass an options object to configure the compiler, for example compiler: { compilationMode: 'annotation' }. The integration's include and exclude options apply, and dependencies and Astro files are excluded.

  Migrating custom Babel transforms

  The integration uses @vitejs/plugin-react v6 and Oxc for JSX and Fast Refresh. The babel integration option has been removed in this major release.

  If you use custom Babel transforms, install @rolldown/plugin-babel and @babel/core, keeping your existing Babel plugins and presets installed:

  pnpm add -D @rolldown/plugin-babel @babel/core

  Move your Babel plugins and presets from react({ babel: ... }) to babel() in vite.plugins. For example, migrate a project using babel-plugin-styled-components from:

  import react from '@astrojs/react';
  import { defineConfig } from 'astro/config';
  
  export default defineConfig({
    integrations: [react({ babel: { plugins: ['babel-plugin-styled-components'] } })],
  });

  To:

  import react from '@astrojs/react';
  import babel from '@rolldown/plugin-babel';
  import { defineConfig } from 'astro/config';
  
  export default defineConfig({
    integrations: [react()],
    vite: {
      plugins: [
        babel({
          plugins: ['babel-plugin-styled-components'],
        }),
      ],
    },
  });

  This also works with react({ compiler: true }). Babel runs before Oxc transforms TypeScript and JSX. The Babel plugin automatically enables parsing for .jsx, .ts, and .tsx files. It does not load babel.config.js or .babelrc files; pass the options directly to babel(). The old babel callback is not supported; use the plugin's overrides and preset hooks for conditional transforms.

  Do not enable babel-plugin-react-compiler on the same components as the Oxc compiler.

• #18044 98c07e1 Thanks @astro-factory! - Fixes a rare issue where ISR pages on Vercel could intermittently be served a cached redirect to a nonsense URL (such as /$0/) instead of the page itself. Pages now render correctly, and requests that can't be resolved to a valid path return a 404 instead of a redirect.

• #18008 a09b328 Thanks @yanthomasdev! - Fixes the immutable Cache-Control rule for hashed assets (/_astro/*) being emitted after the filesystem route handle in .vercel/output/config.json.

• #17946 3fd16ee Thanks @odysseus0! - Fix syntax highlighting for fenced code blocks when raw HTML is enabled.

• #18046 8358d59 Thanks @Princesseuh! - Fixes satteriHeadingIdsPlugin sharing Slugger state across documents when reused as a user hast plugin, which caused headings with the same text in different posts to receive incorrect numeric suffixes

• #17578 7cc0b00 Thanks @renovate! - Fixes a case where rich content diagnostics and snippet edits would not work

• #18036 f4444eb Thanks @astro-factory! - Fixes an incompatibility where @astrojs/mdx v8 could be installed with astro versions that bundle an older @astrojs/markdown-satteri lacking MDX support. Also improves the error message when the processor is too old to suggest updating astro itself.
• Updated dependencies [3fd16ee, 8358d59]:
  • @astrojs/markdown-satteri@0.4.2