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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ChromeOS Flex
ChromeOS Flex, developed by Google, is a free and lightweight Linux distribution based on Gentoo-derived ChromeOS. Unlike ChromeOS which is designed specifically for Chromebook computers, ChromeOS Flex can be installed on most x86_64 devices with a AMD or Intel processors, offering a Chromebook-like experience.