I’m running the Gnome Desktop on Ubuntu 18.04. I installed Duplicati - 184.108.40.206_beta_2019-07-14 and the mono prereqs. It seems to be working ok, with control from the web GUI.
But I keep seeing references to a Tray in the documentation.
There is no evidence of one on my desktop.
Also the install doesn’t seem to have integrated systemd. I’ve been just starting the duplicatii-server manually. Don’t know if thats related.