Can't install forge-1.12.2-14.23.5.2838-installer.jar on Debian 10

[LopezT]

i want to setup a modded Minecraft server based on Minecraft 1.12.2. So I followed a few guides how to do so.

But when it comes to install the forge-1.12.2 installer I get an error message without any detail and feel a bit lost.

My Minecraft version

minecraft@v2202106129756155828:~/server$ java -version
openjdk version "1.8.0_292"
OpenJDK Runtime Environment (AdoptOpenJDK)(build 1.8.0_292-b10)
OpenJDK 64-Bit Server VM (AdoptOpenJDK)(build 25.292-b10, mixed mode)

What happens when I run the installer:

minecraft@v2202106129756155828:~/server$ java -jar forge-1.12.2-14.23.5.2838-installer.jar --installServer
Setting up logger: /opt/minecraft/server/forge-1.12.2-14.23.5.2838-installer.jar.log
java.net.preferIPv4Stack=true
Installing server to current directory
A problem installing the server was detected, server install cannot continue

The error message "A problem installing the server was detected, server install cannot continue" prompts me and there is no explanation what is going on. The installer log says exactly the same.

How can I figure out what the real problem is?