There are multiple options available to identify the running desktop environment on a Linux desktop. Here we discuss two commonly used options. First, execute the following command to check the name of the Desktop Environment.
echo $XDG_CURRENT_DESKTOP
In addition, you can also identify the Desktop by checking the currently running processes. Like the following command will show you the processes running for XFCE or KDE or GNOME desktops.
ps -e | grep -E -i "xfce|kde|gnome"
You will see the results like below. As per the below result, the GNOME desktop is being used on this system.