Installing Gnome Extensions - Wanted for gTile
Usage Refer: https://github.com/gTile/gTile
Refer: https://linuxconfig.org/how-to-install-gnome-shell-extensions-on-ubuntu-20-04-focal-fossa-linux-desktop
$ sudo apt install gnome-shell-extensions
Logoff and Logon Again
Install Firefox extension: https://extensions.gnome.org/
Click on the gnome extension icond in Firefox
Search for gTile and install it