Pardon this newbie question, but I've previously run into serious issues as I wanted to try other desktop environments other than the default one in Ubuntu, precisely because I didn't know how to completely remove some/all of them and get back to the default settings.
I think I ran into these issues because I didn't know which packages to remove as I didn't know which packages were installed at the first place. Commands like
sudo apt-get purge <package name>
still left some applications installed on my system that were originally installed by the original package.
I have a couple of questions here
how do I list all the packages to be installed by installing a specific package and see which of these packages are already installed on my machine (if any)?
I imagine purging only the new packages that were installed by this specific package would get things back to the default settings. Is that right? Is there an easy, quick, and effective way to get things back to the default settings (aside from backing up my data)?