A small correction to the advice about installing the Debian package. Yes, it works, but you need to install version 3.3.8 to fix a problem between Python 3.10 (installed with Ubuntu22) and mailman. So, for me, the commands were:
wget http://ftp.de.debian.org/debian/pool/main/m/mailman3/mailman3_3.3.8-1_all.deb dpkg -i ./mailman3_3.3.8-1_all.deb
...which throws an alert about missing dependencies, that you fix with...
apt install -f
A small correction to the advice about installing the Debian package. Yes, it works, but you need to install version 3.3.8 to fix a problem between Python 3.10 (installed with Ubuntu22) and mailman.
So, for me, the commands were:
wget http:// ftp.de. debian. org/debian/ pool/main/ m/mailman3/ mailman3_ 3.3.8-1_ all.deb 3.3.8-1_ all.deb
dpkg -i ./mailman3_
...which throws an alert about missing dependencies, that you fix with...
apt install -f