Node.js SSE Sandbox Shows Stale Server Response

🐛 bug report

Description of the problem

The sandbox below shows stale server response. The src/index.js file has been moved to index.js (and the main and start in the package.json file updated, including the nodemon src/index.js)

https://codesandbox.io/s/dark-glade-dq2t2?file=/index.js

Repro steps:

1. Start a new Node.js sandbox
2. Drag the src/index.js out of the src directory into the root
3. Update the paths in the package.json in both main and start
4. Change the content in the index.js file
5. See stale content

How has this issue affected you? What are you trying to accomplish?

I want to have the index.js file in the root in a Node.js sandbox.

Trying to create a demo for Shiki: https://github.com/shikijs/shiki/pull/82#issuecomment-686182578

The errors are causing low confidence in the reproducibility and stability of the sandbox.

Link to sandbox: see above.

Your Environment

Reproduce the behavior using the linked CodeSandbox and the listed steps: move src/index.js to index.js, update package.json, and change the file content. Start by checking whether the sandbox still serves the old response after the entry-point changes; done means the root index.js response updates reliably.