Ubuntu 18.04 boot messages

After switching computers (but staying on the same version of Ubuntu), I copied my openvpn configuration (/etc/openvpn) to the new system. And when I booted next time, I received a weird request during boot to type in my username and password. There was no mentioning for what purpose, so I had to guess. Additionally, there is a bug that required me to press twice the Enter key after the username and password. It appeared to be openvpn, which tried - by default - to start up all openvpn configurations that it could find in /etc/openvpn. On my old system I had set it not to start anything automatically. And of course this setting is not in the /etc/openvpn directory, but in /etc/default/openvpn. In order to prevent automatic starting, you need to uncomment the
#AUTOSTART="none" line.
In order to see what process was asking for the password during boot, I needed to see all the boot messages. This is done by pressing Esc shortly after boot to see the grub boot menu (if you have only Ubuntu installed, otherwise you'll see the boot menu by default). You just press e to get into edit mode. Here you edit the line that starts with linux and delete the two words "silent splash". Then you press F10 to start the boot process.