Just installed ubuntu 18.04 in a virtual machine (QEMU/KVM). Cloned the build directory. Changed to build.
When I then run
sudo ./compile.sh
I get
[ o.k. ] Using config file [ /home/robert/armbian/build/userpatches/config-example.conf ]
/home/robert/armbian/build/lib/main.sh: line 136: dialog: command not found
[ error ] ERROR in function source [ main.sh:138 ]
[ error ] No option selected
[ o.k. ] Process terminated
Any idea what I do wrong?