Qubes OS
Qubes OS is a free and open-source, security-oriented operating system for single-user desktop computing. Qubes OS leverages Xen-based virtualization to allow for the creation and management of isolated compartments called qubes.
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KDE Linux
KDE Linux is a user-focused, general-purpose Linux distribution. It is built by KDE and it is meant to showcase the best implementation of everything KDE has to offer, using the most advanced technologies.