[Feature request]: Option to prevent Flatpak app opening browser/other application

[mariomadproductions]

Checklist

• [X] I agree to follow the Code of Conduct that this project adheres to.
• [X] I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Suggestion

Some programs (e.g. Discord) open your browser to a special URL in order to get your discord login info from the browser session. This is not a major privacy/security risk as this presumably requires the discord server to "cooperate", but it does seem wrong that an app can open arbitrary URLs without user permission (discord does this on startup without asking). I think it would be a good idea if this could be prevented somehow, using the flatpak per-app restrictions that users enable.