I guess, it's the boolean preference item "network.cookie.noPersistentStorage", for your query:

• you can try Customize Firefox using Group Policy (Windows);
• if you're not using Windows, Customize Firefox using policies.json.

For deeper information: Preferences API, A brief guide to Mozilla preferences.

Also, WARNING from the moderator team: Changing some Firefox preferences in the about:config page can sometimes break Firefox or cause strange behavior. You should only do this if you know what you're doing. Please read Firefox advanced customization and configuration options to learn more.

I guess, it's the boolean preference item "network.cookie.noPersistentStorage", for your query:

• you can try Customize Firefox using Group Policy (Windows);
• if you're not using Windows, Customize Firefox using policies.json.

For deeper information: Preferences API, A brief guide to Mozilla preferences. Also, WARNING from the moderator team: Changing some Firefox preferences in the about:config page can sometimes break Firefox or cause strange behavior. You should only do this if you know what you're doing. Please read Firefox advanced customization and configuration options to learn more.

Thank you for your response. I tried the solution, and now the permission is blocked. However, when a user opens ChatGPT, they are still asked whether they want to allow "saving persistent storage." If they click "yes," the permission is set to "allowed."

Is there any way to completely stop this from happening, or is there a specific GPO setting that disables at least the popup that asks users if they want to save persistent data?

Thanks again for your help!

For the permission, it's the numeric "permissions.default.persistent-storage".

Correcting my words:

• if you want to make persistent storage permission denied by default, make it 2;
• if you want to disable persistent storage at all, make "network.cookie.noPersistentStorage" true.

Thank you for your patience reading, please let us know if you have any further questions!