In Firefox, I want to disable the pop up that prevents leaving the page when it detects something not saved, which is the setting user_pref("dom.disable_beforeunload", true);
Now, according to the config wizard, the way to do this is to have a text file on an external server linked in the config with browser_preferences.
However, it's just absolutely not practical to have an external host for a single line text file just for this config. Even making a VM ourselves is just a waste of resources.
So the questions are:
A) Is it actually the only way to be able to modify those browser settings?

C) If so, how do I make that happen? I'm guessing by using the permanence setting.
Thanks