MiniOxygen encountered an error while running your app's entry point

[Emmanuel-1002]

What is the location of your example repository?

No response

Which package or tool is having this issue?

Hydrogen

What version of that package or tool are you using?

latest from npm

What version of Remix are you using?

No response

Steps to Reproduce

npm create @shopify/hydrogen@latest
Javascript
NPM yes
Tailwind

Then:
h2 upgrade

Then:
npm run dev

Expected Behavior

Should open page with front

Actual Behavior

error
│ │
│ MiniOxygen encountered an error while running your app's entry point: │
│ │
│ SyntaxError: Unexpected token '<', "<!DOCTYPE "... is not valid JSON

NPM version: v10.8.2
Node version: v20.16.0

[rogerogers]

The issue might be that port 3000 on your local machine is being used by another program, such as Grafana. This is what happened in my case.

[NicolasTMS]

The issue might be that port 3000 on your local machine is being used by another program, such as Grafana. This is what happened in my case.

I don't have anything else running. One week ago I got this error only sometimes. But since that I always got this error. So impossible to run application in "Dev" mode

[Emmanuel-1002]

It was the PORT 3000 that was already used ! Thanks :)
Will be nice to add different port on the ENV / also say in the console if we would like to open using another port (like npm run dev on react project)

[frandiox]

The dev server should already start in a different port if 3000 is in use. However, there might be a bug in the way MiniOxygen communicates with the Vite server when there are more than 1 Vite servers up (e.g. 3000 and 3001). Leaving this open for now while we try to reproduce it.