Vanilla OS
Vanilla OS, a fixed-release distribution based on Debian (formerly Ubuntu, prior to version 2) with the GNOME desktop, is an immutable operating system. The core parts of the system are locked down to prevent unwanted changes and corruption from third-party applications or a faulty update.
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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.