Tutorial on how to remove snap support and install flatpaks in Kubuntu. I did this on my recent Kubuntu 23.10 installation. Also works for Lubuntu and Ubuntu Studio. Not supported on any other Ubuntu variants or distros based on Ubuntu.
Installing Firefox deb package:
Script to get rid of Snap - Kubuntu Forums
Purpose of this script This is a little helper script for Kubuntu™ users who want to get rid of and block Snap entirely (like Linux Mint does), including the Firefox Snap from 22.04 onwards. It has been tested many times with Kubuntu™ 20.04, 22.04, 23.04 and 23.10. I hope you find the script...
www.kubuntuforums.net
Installing Firefox deb package: