Thunar is the file manager included in Xfce, a free and open source Desktop Environment which implements the traditional desktop metaphor, and has become the favorite of many users which switched to it when the GNOME project introduced the GNOME shell. Thunar is light on resources but doesn’t lack functionalities which can be extended further by creating custom actions.
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How to customize the SDDM display manager on Linux
SDDM (Simple Desktop Display Manager) is a modern, free and open source Display Manager available on Linux and other Unix platforms like FreeBSD. It works both with X11 and Wayland, and is based on QtQuick, a framework to build QML applications. SDDM allows a great degree of customization and; thanks to this, a lot of custom themes are available for it.
How to customize i3status on Linux
I3 is one of the most used tiling window managers on Linux. A tiling window manager arranges windows in a non-overlapping way: this allows us to use screen space efficiently, but can require a little bit of time to get used to.