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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Peppermint OS
Peppermint OS is a Debian- and Devuan-based (previously a Lubuntu-based) Linux distribution that aims to be fast and easy on system resources. By employing its Site Specific Browser, Peppermint integrates seamlessly with cloud and web-based applications.