1. Download and Install the Extension Package

Download the appropriate package for your distribution

The package is called himmelblau-qr-greeter. Follow your distribution’s instructions for installing system packages.

1. Enable the Extension for the GDM User

Since the extension runs on the GDM (login) screen, you must enable it as the gdm user. Run the following commands:

1. Open a shell as the gdm user:

   sudo machinectl shell gdm@ /bin/bash

2. Enable the extension for GDM:

   gsettings set org.gnome.shell enabled-extensions "['qr-greeter@himmelblau-idm.org']"

3. Exit the shell:

   exit

4. Restart GDM

To apply the changes, restart GDM:

sudo systemctl restart gdm3

After these steps, the Himmelblau QR Greeter extension will be active on your login and lock screens.