Hello.

I tried installing the Minecraft launcher on Debian 10 and dpkg threw the following error.

dpkg: dependency problems prevent configuration of minecraft-launcher:
{{ minecraft-launcher depends on oracle-java8-installer | openjdk-8-jre; however:}}
{{ Package oracle-java8-installer is not installed.}}
{{ Package openjdk-8-jre is not installed.}}
{{ minecraft-launcher depends on gconf-service; however:}}
{{ Package gconf-service is not installed.}}
{{ minecraft-launcher depends on libgconf-2-4 (>= 2.31.1); however:}}
{{ Package libgconf-2-4 is not installed.}}
{{ minecraft-launcher depends on libpango1.0-0 (>= 1.14.0); however:}}
{{ Package libpango1.0-0 is not installed.}}
{{ minecraft-launcher depends on xdg-utils (>= 1.0.2); however:}}
{{ Package xdg-utils is not installed.}}
{{ minecraft-launcher depends on libcurl3 | libcurl4; however:}}
{{ Package libcurl3 is not installed.}}
{{ Package libcurl4 is not installed.}}

dpkg: error processing package minecraft-launcher (--install):
{{ dependency problems - leaving unconfigured}}
Processing triggers for bamfdaemon (0.5.4-1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for desktop-file-utils (0.23-4) ...
Processing triggers for mime-support (3.62) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Errors were encountered while processing:
{{ minecraft-launcher}}

Then I tried installing these needed packages manually from apt. However, the packages oracle-java8-installer and openjdk-8-jre are both non-existent on Debian 10's repositories, both free and nonfree (no backports).

The dependencies were set to manually installed, so I tried again. This time, I installed the default-jre package to substitute the needed JRE. While dpkg did throw another error, the launcher works.

This seems to mostly be an error with Debian 10 having removed version 8 JREs in place of the version 11 OpenJDK JRE, whilst the Minecraft package still depends on the old (and now removed) version 8. The package openjdk-11-jre does exist and is what default-jre installed.