Linux does not need extensions for the most part. It knows that it is a text
file by looking at the contents. The problem is that scripts are text files
and Linux relies on them heavily. In KDE, text files open in Kate, a text
editor, when you click on them. You have to change the permissions in order
to have them execute. This is the opposite of GNOME which wants to run the
script first. So, you could give KDE a try.