Firefox on Linux:  Cross-Origin Request Blocked

I can’t use FastPlayground on Firefox 117 on Linux. The reason seams to be Cross-Origin Request Blocked.
Full error:

```
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource
at https://faustservice.grame.fr/targets.
(Reason: CORS header ‘Access-Control-Allow-Origin’ missing). Status code: 502.
```