I find pretty irritating dealing with Telegram under Ubuntu. I run 18.04.1, I guess I picked the official Telegram client from Ubuntu Software... for a start, there a two clients in there. One from the Ubuntu store does not auto-update and the other does not recognize your theme/icon set/shell (see screenshot)...
Then you have as well the tar.xz on the official Telegram website that creates a double entry in the Show Applications menu and lives in your home folder for whatever reason. I believe there are also some esoteric unofficial clients you can find around.
So, it's a mess. I just want an official client who blends in well with your theme and auto updates itself to the latest version. Something normal, really. Anyone has some clues? Thanks!