There also this cool text editor, simple and fast, called Pluma and available on Ubuntu Mate which I really enjoyed using.
Xed is a fork of pluma, and is an X-App included with Linux Mint. (Seems to be under very active development.) [0]
Pluma is a fork of gedit2, seems mostly to integrate it nicer with MATE. (Seems to be under very active development.) [1]
gedit is also still around, and is still "Gnome's text editor", and seems to be under very active development. [2]
[0] https://github.com/linuxmint/xed