Kubuntu
Kubuntu is a free, user-friendly Linux distribution based on KDE's desktop software and on the Ubuntu operating system. It has a biannual release cycle.
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TUXEDO OS
TUXEDO OS is an Ubuntu-based distribution developed in Germany by TUXEDO Computers GmbH, designed and optimised for the company's own range of Linux-friendly personal computers and notebooks. The distribution uses KDE Plasma as the preferred desktop.