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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Synex
Synex is a GNU/Linux distribution based on Debian's "Stable" branch, developed with the official Debian Live Build tool. It offers four separate desktop options with GNOME, LXDE, KDE Plasma and Xfce, all of which are composed of a rather frugal set of applications in its default state, without any development tools or offices suites.