Hello, you might have to do this manually for each profile -- if you wish to submit a feature request, do so at https://bugzilla.mozilla.org -- Once there you will need to create an account. When you're registered follow the documentation for bug filing to get you started.

Is there a reason you want this?

We are running Firefox Quantum on Windows Server 2012R2 where all users must have same homepage when they open Firefox browser

I called for more help.

You can use the mozilla.cfg file in the Firefox program folder to set or lock preferences and run privileged JavaScript code.

The mozilla.cfg file needs to be in the main Firefox program folder.

These functions can be used in the mozilla.cfg file:

defaultPref();	// set new default value
pref();	// set pref, allow changes in current session
lockPref();	// lock pref, disallow changes

This requires a local-settings.js file in the "defaults/pref" folder where the channel-prefs.js file is located that specifies to use mozilla.cfg.

//
pref("general.config.filename", "mozilla.cfg");
pref("general.config.obscure_value", 0);

The mozilla.cfg and local-settings.js files need to start with a comment line (//).

See Configuration:

• https://developer.mozilla.org/en-US/Firefox/Enterprise_deployment

See also:

• http://mike.kaply.com/2012/03/16/customizing-firefox-autoconfig-files/