Error with SSL Interception HTTP Proxy

[Dennis14e]

Software:

• Debian Linux
• Apache 2.4.38
• PHP-FPM 8.1.27
• Contao-Manager 1.8.4

I specify the environment variables "HTTP_PROXY" and "HTTPS_PROXY" in the Apache Config.
With an HTTP proxy that does not intercept SSL, everything works (I can install/update packages).
It does not work with an HTTP proxy that intercepts SSL. The explicit proxy from FortiGate FortiGuard is used. Everything looks fine in the firewall log.
The CA certificate used is located under /usr/local/share/ca-certificates/ and the command "update-ca-certificates" was then executed. The certificate is therefore part of the file "/etc/ssl/certs/ca-certificates.crt".
An update seems to work via the CLI, but not via the web interface.

Error message:

HTTP request to https://www.composer-resolver.cloud/jobs failed with status code 201 ()
Error handling the Composer Resolver Cloud. Please try again later.

[fritzmg]

@Dennis14e do you even need the Composer Resolver Cloud? The Composer Resolver Cloud is only necessary for environments with severely limited memory resources. If your environment has enough memory you can disable the Composer Resolver Cloud in the server settings of the Contao Manager.

[Dennis14e]

@fritzmg I didn't know that I could deactivate the Composer Resolver Cloud, it was activated by default.
After deactivating the function, updating packages works again.
The question is of course whether the combination of Resolver Cloud and SSL Interception should work/not work.

[aschempp]

if it can work, it wouldn't harm. But I have no idea what needs to be changed, and very little time to invest into such an edge case 🙈