Firefox Setup: how to use existing profile

Question

In order to prepare a classroom for training, I run a Windows batch file which, among other things, runs the Firefox Setup application.

There is an existing profile folder which has everything the way I want it, so I always choose not to restore default settings.

However, when Firefox restarts, it always starts with a new default profile.

I can manually delete the profile and files using the Profile Manager:

… but that is tedious for a classroom, especially when I need to do it repeatedly.

Ho can I run the installer and get it to use the existing default profile?

Answer 1

Assume that default-release is the one created by the upgrade process, and default profile is the one you want to use after the upgrade, just add one more line of code to your batch file:

firefox.exe -P default 

This starts Firefox using the profile called default.

It seems Firefox stores all profile names, paths and which one to use during startup in %appdata%\Mozilla\Firefox\profiles.ini, maybe you can do this:

1. Backup the above file prior to upgrade 
2. Restore the file after upgrade 

If you do this, the actual profile folder would still be there, maybe you can remove it by something like rmdir /Q /S %appdata%\Mozilla\Firefox\Profiles\*.default-relase.