Ubuntu 18.04 Find Mouse Button
You are Welcome! The Tutorial Shows You Step-by-Step How to Find the Mouse Button ID in Ubuntu 18.04 Bionic LTS GNU/Linux.
And the Xev Ubuntu Bionic Tool creates a Window and then asks the X server to Send it Events whenever anything Happens to the window (such as it being Moved, Resized, Typed in, Clicked in, etc.).
Finally, the Guide includes detailed instruction on How to Map the Mouse Button on Ubuntu Desktop.
1. Launching Terminal
How to Quick Start with Command Line on Ubuntu LinuxCommand Line Ubuntu Linux Quick Start Guide
First Update the Apt Repo Sources with:
sudo apt update