Linux Cafe

So I recently tried Mailspring, and decided it was not for me. So i found it on the menu, right clicked and selected uninstall (Mint Cinnamon).

Now I am concerned if all files and cache have been deleted. I then ran "apt remove mailspring" ( My firt stime typing my own command on the terminal by memory!!!! - i feel so nerdy in a good way!!). Anyway, that could not locate package.

Should I be concerned of it having left any files behind, or am I safe to assume that all files have been deleted?

The reason why I am asking is, that the program (mailspring) was running when I deleted it though the menu and kept running after deletion! I just couldn't find it on the menu any longer.