How to install Github Desktop for Ubuntu & Debian?

Step 1:

Use the wget command followed by the URL of the .deb file from the GitHub desktop of the Shiftkey Github repository. Shifykey is maintained by Brendan Forster, one of the Github contributors.
Note: Updated link to Github Desktop 2.9

sudo wget https://github.com/shiftkey/desktop/releases/download/release-2.9.0-linux2/GitHubDesktop-linux-2.9.0-linux2.deb

Step 2 :

Install gdebi with the following command, which will help you install local deb packages and resolve and install their dependencies.

sudo apt-get install gdebi-core

Step 3:

After installing gdebi, use gdebi to install the GitHubDesktop client with the following command.

sudo gdebi GitHubDesktop-linux-2.9.0-linux2.deb

Alternate methods to install, after Step 1 :

You can also use the dpkg or apt commands.

Method 1:

sudo dpkg -i GitHubDesktop-linux-2.9.0-linux2.deb

sudo apt-get install -f

Method 2:

sudo apt install ./GitHubDesktop-linux-2.9.0-linux2.deb