Can't get any sandbox to run due to CORS errors

[kswedberg]

🐛 bug report

Preflight Checklist

• [x] I have read the Contributing Guidelines for this project.
• [x] I agree to follow the Code of Conduct that this project adheres to.
• [x] I have searched the issue tracker for an issue that matches the one I want to file, without success.

Description of the problem

Can't see the preview in any sandbox/devbox due to a bunch of CORS errors. Tried in Chrome, Edge, Safari, and Firefox.

Here's a screenshot of what it looks like in Firefox:

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

To Reproduce

Take a look at this "devbox" (it was converted from sandbox to devbox when I made it public. doesn't affect the problem): https://codesandbox.io/p/devbox/s34nmy

I used the "JavaScript" sandbox from the Popular tab to create it. I tried one with just HTML + CSS, but that didn't work either.

Link to sandbox: codesandbox.io/p/devbox/s34nmy

Your Environment

Software	Name/Version
Сodesandbox	current
Browser	any
Operating System	Mac