[vite] failed to connect to websocket

[mickosi]

Describe the bug

client:765 [vite] failed to connect to websocket.
your current setup:
  (browser) localhost:3000/app/ <--[HTTP]--> localhost:5173/app/ (server)
  (browser) localhost:3000/app/ <--[WebSocket (failing)]--> localhost:5173/app/ (server)

Reproduction

https://github.com/mickosi/nuxt-issue2/blob/main/app/pages/index.vue

Steps to reproduce

No response

System Info

System:
    OS: Linux 6.11 Ubuntu 24.10 24.10 (Oracular Oriole)
    CPU: (4) x64 Intel(R) Pentium(R) CPU
    Memory: 528.65 MB / 3.69 GB
    Container: Yes
    Shell: 5.9 - /usr/bin/zsh
  Binaries:
    Node: 20.16.0 - /usr/bin/node
    Yarn: 1.22.22 - /usr/bin/yarn
    npm: 9.2.0 - /usr/bin/npm
    pnpm: 10.15.0 - /usr/bin/pnpm
    bun: 1.2.5 - /usr/local/bin/bun
    Watchman: 4.9.0 - /usr/bin/watchman
  Browsers:
    Chromium: 138.0.7204.183

nuxt 3

Used Package Manager

npm

Logs

No response

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 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.

[wmodden]

I'm getting the same error, I'm trying to provide a codesandbox for reproduction

[Heartnett]

oven-sh/bun#18737

[mickosi]

oven-sh/bun#18737 (comment)