Base URL with custom protocol is prefixed with slash

Describe the bug

After setting custom protocol, built dist files have a leading slash in path.

export default defineConfig({
  base: 'app://',
});

(my use-case for custom protocol is to load app in Electron).

Reproduction

https://stackblitz.com/edit/vitejs-vite-bu8uph?file=dist/index.html

System Info

Binaries:
    Node: 16.13.0 - C:\Program Files\nodejs\node.EXE    
    Yarn: 1.22.11 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 8.1.0 - C:\Program Files\nodejs\npm.CMD

Used Package Manager

yarn

Logs

No response

Validations

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• Read the Contributing Guidelines.
• Read the docs.
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• The provided reproduction is a minimal reproducible example of the bug.

[patak-dev]

I think we should close this though, I prefer we get a real use case to justify changing the isExternal logic. Let’s wait til then.

[SnosMe]

Turns out, I don’t need to change the base path at all. Really feel stupid for not trying this from the beginning (considering it’s the default setting). 😄 Using app:// was a workaround for something in Chromium or Electron or VueCLI and now (2 years later) is no longer needed.

So yeah, although I no longer affected by this, it’s still a bug.