In Terminal menu, inside the gnome-terminal, I have the option "Change Profile". What is it for? And why is it disabled?
2 Answers
The Profile is just a presets of how your terminal session should behave. You can create a profile for let us say, when working at night by adding some different colors on terminals output, you can use different fonts if you want so etc.
To add a little bit to @Salih Emin answer, if you don't have yet created at least a second profile, there is nothing to switch to, so "Change profile" is disabled.