I had a look in my
/etc/apt/sources.list and it had an entry for
buster, so I added the line for Veyon Buster:
deb http://ppa.launchpad.net/veyon/stable/ubuntu bionic main
I then tried to run the command
sudo add-apt-repository ppa:veyon/stable
but there is no
add-apt-repository on my Raspberry and I could not install that with
sudo apt install.
sudo apt-get update
does not work, because there are keys missing, so the source is not trusted. What am I missing?