I've been trying to get remote desktop working with my installation of Ubuntu 18.04, but the toggle doesn't seem to stay on. I go to settings, then Sharing and switch the toggle to on, then I select Desktop Sharing and try to turn the second toggle on, but it keeps springing back to off.
My machine was recently upgraded from 14.04 to 16.04, and now to 18.04 as the OS recommended that I upgrade.
After giving cmak.fr's suggestion a try first thing this morning, I realised that the Networks box at the bottom of the dialog shows that no networks are selected. I definitely have a connections, so I'm wondering if this is where the root of the issue lies.
I've tried the suggestion here: Screen-Sharing "no network selected for sharing" problem in unity control center (18.04), but I still haven't been able to make it work through the dialog.