Dev Server says "Upgrade Required", browser has CORS-issues since Vite version 2.9.0

Describe the bug

Hello Vite!

I’m the author of this plugin for Vite and Silverstripe CMS, this plugin for CakePHP, and I use this configuration.

Until now, everything worked fine with the dev server, hot module replacement etc. However, after running yarn upgrade i noticed that the dev server is not working anymore. The browser is complaining about cors-issues - see screenshot below:

I tried to downgrade vite step by step and the issue seems to be present from version 2.9.0. Is there any configuration that I missed which has to be present?

As I use Vite in php apps, I serve my PHP with MAMP (e.g. https://my-domain.local) and the js from vite gets served by the vite dev server from localhost:3000, through this configuration:

    server: {
        hmr: {
            protocol: 'ws',
            host: 'localhost',
            port: 3000,
        },
    },

When accessing one of the localhost urls, I now only get an Upgrade required warning. In the network tab I see that the browser got a http 426 response from the dev server, similar to this issue: https://github.com/vitejs/vite/issues/5770

However, reinstalling did not solve the problem. I have now locked the version in package.json to vite 2.8.6 which works for now, but I hope I will be able to keep Vite up to date in the future.

If this is a bug, I am happy to help with further information. Otherwise it would be great to get a hint about how to solve this problem.

Reproduction

https://github.com/brandcom/silverstripe-vite

System Info

System:
    OS: macOS 12.3.1
    CPU: (8) arm64 Apple M1
    Memory: 158.61 MB / 16.00 GB
    Shell: 5.8 - /bin/zsh
  Binaries:
    Node: 17.0.1 - /opt/homebrew/bin/node
    Yarn: 1.22.18 - /opt/homebrew/bin/yarn
    npm: 8.3.0 - /opt/homebrew/bin/npm
  Browsers:
    Brave Browser: 102.1.39.120
    Chrome: 102.0.5005.115
    Firefox: 101.0.1
    Safari: 15.4
  npmPackages:
    @vitejs/plugin-legacy: ^1.8.2 => 1.8.2 
    @vitejs/plugin-vue: ^2.3.3 => 2.3.3 
    vite: 2.8.6 => 2.8.6

Used Package Manager

yarn

Logs

vite --debug
  vite:config bundled config file loaded in 18.10ms +0ms
  vite:config using resolved config: {
  vite:config   plugins: [
  vite:config     'vite:pre-alias',
  vite:config     'alias',
  vite:config     'vite:modulepreload-polyfill',
  vite:config     'vite:resolve',
  vite:config     'vite:html-inline-proxy',
  vite:config     'vite:css',
  vite:config     'vite:esbuild',
  vite:config     'vite:json',
  vite:config     'vite:wasm',
  vite:config     'vite:worker',
  vite:config     'vite:worker-import-meta-url',
  vite:config     'vite:asset',
  vite:config     'vite:vue',
  vite:config     'vite:legacy-env',
  vite:config     'vite:define',
  vite:config     'vite:css-post',
  vite:config     'vite:client-inject',
  vite:config     'vite:import-analysis'
  vite:config   ],
  vite:config   build: {
  vite:config     target: [ 'es2019', 'edge88', 'firefox78', 'chrome87', 'safari13.1' ],
  vite:config     polyfillModulePreload: true,
  vite:config     outDir: './public/',
  vite:config     assetsDir: 'build',
  vite:config     assetsInlineLimit: 4096,
  vite:config     cssCodeSplit: true,
  vite:config     cssTarget: [ 'es2019', 'edge88', 'firefox78', 'chrome87', 'safari13.1' ],
  vite:config     sourcemap: false,
  vite:config     rollupOptions: { input: './public_src/main.ts' },
  vite:config     minify: 'esbuild',
  vite:config     terserOptions: {},
  vite:config     write: true,
  vite:config     emptyOutDir: false,
  vite:config     manifest: true,
  vite:config     lib: false,
  vite:config     ssr: false,
  vite:config     ssrManifest: false,
  vite:config     reportCompressedSize: true,
  vite:config     chunkSizeWarningLimit: 500,
  vite:config     watch: null,
  vite:config     commonjsOptions: { include: [Array], extensions: [Array] },
  vite:config     dynamicImportVarsOptions: { warnOnError: true, exclude: [Array] }
  vite:config   },
  vite:config   server: {
  vite:config     preTransformRequests: true,
  vite:config     hmr: { protocol: 'ws', host: 'localhost', port: 3000 },
  vite:config     fs: { strict: true, allow: [Array], deny: [Array] }
  vite:config   },
  vite:config   define: {
  vite:config     __VUE_OPTIONS_API__: true,
  vite:config     __VUE_PROD_DEVTOOLS__: false,
  vite:config     'import.meta.env.LEGACY': false
  vite:config   },
  vite:config   ssr: { external: [ 'vue', '@vue/server-renderer' ] },
  vite:config   configFile: '/Users/pascalschneider/Sites/xyz.local/vite.config.ts',
  vite:config   configFileDependencies: [ 'vite.config.ts' ],
  vite:config   inlineConfig: {
  vite:config     root: undefined,
  vite:config     base: undefined,
  vite:config     mode: undefined,
  vite:config     configFile: undefined,
  vite:config     logLevel: undefined,
  vite:config     clearScreen: undefined,
  vite:config     server: {}
  vite:config   },
  vite:config   root: '/Users/pascalschneider/Sites/xyz.local',
  vite:config   base: '/',
  vite:config   resolve: { dedupe: undefined, alias: [ [Object], [Object] ] },
  vite:config   publicDir: '/Users/pascalschneider/Sites/xyz.local/public',
  vite:config   cacheDir: '/Users/pascalschneider/Sites/xyz.local/node_modules/.vite',
  vite:config   command: 'serve',
  vite:config   mode: 'development',
  vite:config   isProduction: false,
  vite:config   preview: {
  vite:config     port: undefined,
  vite:config     strictPort: undefined,
  vite:config     host: undefined,
  vite:config     https: undefined,
  vite:config     open: undefined,
  vite:config     proxy: undefined,
  vite:config     cors: undefined,
  vite:config     headers: undefined
  vite:config   },
  vite:config   env: { BASE_URL: '/', MODE: 'development', DEV: true, PROD: false },
  vite:config   assetsInclude: [Function: assetsInclude],
  vite:config   logger: {
  vite:config     hasWarned: false,
  vite:config     info: [Function: info],
  vite:config     warn: [Function: warn],
  vite:config     warnOnce: [Function: warnOnce],
  vite:config     error: [Function: error],
  vite:config     clearScreen: [Function: clearScreen],
  vite:config     hasErrorLogged: [Function: hasErrorLogged]
  vite:config   },
  vite:config   packageCache: Map(0) {},
  vite:config   createResolver: [Function: createResolver],
  vite:config   optimizeDeps: {
  vite:config     esbuildOptions: { keepNames: undefined, preserveSymlinks: undefined }
  vite:config   },
  vite:config   worker: {
  vite:config     format: 'iife',
  vite:config     plugins: [
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object],
  vite:config       [Object], [Object]
  vite:config     ],
  vite:config     rollupOptions: {}
  vite:config   }
  vite:config } +3ms
  vite:deps Hash is consistent. Skipping. Use --force to override. +0ms

  vite v2.8.6 dev server running at:

  > Local: http://localhost:3000/
  > Network: use `--host` to expose

  ready in 129ms.

Validations

• Follow our Code of Conduct
• Read the Contributing Guidelines.
• Read the docs.
• Check that there isn’t already an issue that reports the same bug to avoid creating a duplicate.
• Make sure this is a Vite issue and not a framework-specific issue. For example, if it’s a Vue SFC related bug, it should likely be reported to https://github.com/vuejs/core instead.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion or join our Discord Chat Server.
• The provided reproduction is a minimal reproducible example of the bug.

[patak-dev]

@passchn it would be helpful if you could review and comment on https://github.com/vitejs/vite/pull/7977, we would like to move forward with this change in v3

[sapphi-red]

Oh, that’s true. It needs server.hmr settings.