Document Vite workaround for browser build (#5209)

docs/migration/index.md

@@ -22,6 +22,8 @@ For larger configs, it can make sense to update to `rollup@3.29.4` first, add th
 
 Rollup now includes native code that is automatically installed (and removed) as an [optional npm dependency](https://docs.npmjs.com/cli/v10/configuring-npm/package-json#optionaldependencies) if your platform and architecture is supported. More precisely, Rollup has a list of `optionalDependencies`, each of which only install on a specific [`os`](https://docs.npmjs.com/cli/v10/configuring-npm/package-json#os) and [`cpu`](https://docs.npmjs.com/cli/v10/configuring-npm/package-json#cpu). If your system is not supported, you will receive an error message when starting Rollup that will tell you about your platform and architecture and gives you a list of supported ones. In that case, you can instead use `@rollup/wasm-node` as a platform-independent drop-in replacement.
 
+The browser build (`@rollup/browser` on NPM) now relies on a WASM artifact that needs to be provided as well. If you are using the browser build with Vite, you'll need to add `"@rollup/browser"` to `optimizeDeps.exclude`, otherwise `npm run dev` fails with an invalid path to the `.wasm` file (see also [vitejs #14609](https://github.com/vitejs/vite/issues/14609)). Otherwise it should work without any specific intervention.
+
 Otherwise, an obvious change is that Rollup now uses url-safe base64 hashes in file names instead of the older base16 hashes. This provides more hash safety but means that hash length is now limited to at most 22 characters for technical reasons.
 
 When bundling CLI apps, Rollup will now automatically preserve shebang comments in entry files if the output [`format`](../configuration-options/index.md#output-format) is `es` or `cjs`. Previously, you would have needed to add the comment via a plugin.