Lubuntu
Lubuntu is a variant of Ubuntu that uses the LXQt desktop environment. (Versions prior to 18.10 shipped with the LXDE desktop.) It includes essential applications and services for daily use, including office suite, PDF reader, image editor and multimedia players.
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CuerdOS
CuerdOS is a Debian-based GNU/Linux distribution with focus on stability, efficiency and performance. It comes with a series of optimisations, such as performance and memory consumption improvements.