Linux Shout published a quick tutorial about how to disable super/win key in Ubuntu 20.04 or 18.04.

How to Disable Super or Win Key in Ubuntu 20.04 or 18.04

Simple steps to disable the Super or Win logo key on Ubuntu 20.04, 18.04 LTS Linux distros using Gnome Tweaks tool's keybaord & mouse setting

How to Disable Super or Win Key in Ubuntu 20.04 or 18.04 - Linux Shout