GNU/Linux Ubuntu 20.04 Installing GNOME Tweaks Guide
How to Install GNOME Tweaks (formerly GNOME Tweak Tool) in Ubuntu 20.04 Focal LTS GNU/Linux desktop.
And Gnome Tweaks for Ubuntu 20.04 is a Graphical interface for advanced GNOME 3+ Settings.
Moreover, Tweaks is Designed for GNOME Shell but Can be Used in other desktops. Only a few Features will be Missing when Tweaks is run on a Different desktop.
Finally, this guide includes detailed instructions about to Installing Best GNOME Extensions on Ubuntu.

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1. Terminal Quick Start
How to Quick Start with Command Line on Ubuntu
First, Update the Apt Repo Sources with:
sudo apt update
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