Upgrade nano editor on Raspberry Pi OS (Raspbian)

Today I realised that my Raspberry Pi is running an old version (v3.2) of nano that was released 3 years ago. The latest version is currently v5.9. Huge difference.

So I decided to upgrade the nano editor on my Raspberry Pi.

Let's see how I did it:

1. Check the current version of the nano
   nano -V
   
   
2. Open the "sources.list" file with our favorite editor :)
   sudo nano /etc/apt/sources.list
   
   
3. Comment all lines, and add these ones
   deb http://raspbian.raspberrypi.org/raspbian/ testing main contrib non-free rpi
   deb http://mirrordirector.raspbian.org/raspbian testing main contrib non-free rpi
   
   
4. Run apt update for refresh the list of available packages
   apt update
   
   
5. Upgrade ONLY the nano - DO NOT update everything, this repository contains packages with testing status. The RPi can be unstable after installing all packages!
   sudo apt-get install --only-upgrade nano
   
   
6. Check the nano version again
   nano -V
   
   
7. Comment both added lines in sources.list file, and uncomment the original lines
   sudo nano /etc/apt/sources.list
   
   
8. Enjoy your upgraded nano editor :)