JVM optimization arguments (OpenJDK support)

[Ecconia]

I basically copyied the JVM optimizations of the legacy launcher. They work with an official Java. But not with OpenJDK.

Imo there should be an option to choose some optimizations, but I am not very familiar with them yet.

Workaround: Just comment the ones out which don't work. Or add your own ones.

[MaxBr5]

I could if you switch to gradle, I suck at maven.

[Ecconia]

Gradle is like way more complicated than maven... (setup usage understanding) - it is much more powerful too though (not needed in this project).

Build project with maven: mvn clean package
That is all it needs to build the project. And ofc installed maven. But a download with the executable is sufficient.