Cannot access the demo apps

[Robin-Sayer]

When I go to the demo apps such as this one https://codesandbox.io/s/first-react-app-start-7ec9fd I can see the code, but the app itself displays only as a white screen. Opening the app in a new tab and checking the console, there are a lot of console errors, mostly relating to Cross-Origin Request Policy saying that access to scripts has been blocked, and lots of "failed to load resource" errors.
For instance:
Access to script at 'https://codesandbox.io/static/js/vendors~app~codemirror-editor~monaco-editor~sandbox.f80b3d7b3.chunk.js' from origin 'https://7ec9fd.csb.app' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

[Robin-Sayer]

It also looks like this "simply type react.new into your browser and you can immediately create a React project" thing doesn't work, as it now fails and tells me I'm not signed in to codesandbox.io, a site which seems to expect me to pay to sign up (which was not mentioned anywhere on this course, which just said that you could type in react.new and immediately get started with react).

Even the free trial button on codesandbox.io gives me an error when I click it of

Application error: a server-side exception has occurred (see the server logs for more information).

Digest: 3016558034

Are all the interactive aspects of this course simply broken now for anyone without a paid subscription to codesandbox? (At least, without creating the projects locally and doing it all that way.)