The MATE project started as a fork of GNOME 2 long back in 2011 following the poor reception of GNOME 3. Since then, it has come a long way and the latest MATE 1.22 release continues to improve the different desktop components.
The biggest change in this release is Wayland-related work. The developers have reworked tons of code to make sure that things work with the Wayland backend. Specifically, it involves a complete revamp of the display applet to control the monitor in a better way.
Work has also been done to port mate-menus library, python-caja plugin libraries, eye of MATE to Python 3. There are other changes in apps like Calculator, file manager, and Engrampa as well.
I won’t be going into the details of all the changes as you can find them here in the announcement post. There, you can also find the complete changelog as well.
If you’re currently running some other desktop environment on your distro and you wish to try out MATE 1.22, you can follow their detailed guide on their website. For instance, you can install MATE in the following manner on Ubuntu.
apt-get install mate-desktop-environment
Alternatively, if you’re already running MATE on your distro, you can either use the update manager on your OS to check for updates or directly perform the update from the terminal.