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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NebiOS
NebiOS is an Ubuntu-based desktop Linux distribution with a custom Wayland compositor called NebiDE (based on Wayfire). It features various user interface enhancements, an initial setup module called OOBE, the NebiOS App Runtime (napp-runtime) portable application format with bubblewrap containerization, improved gaming performance with Steam Proton integration, a kernel switcher for easy multi-kernel installation, and the Wine compatibility layer for running some Windows applications.