the problem was resolved for the Manjaro-Kde plasma system.
To test it, you must run sweet home 3d through the terminal:

command line to execute:
SWEETHOME3D_JAVA3D = 1.5 sweethome3d

link to the open topic in manjaro where you can find more information.

https://forum.manjaro.org/t/solved-sweet ...

so how can i offer useful data to solve this?
believed that it was just a java bug in the manjaro repositories (arch-linux) and that updating or replacing the repository would suffice.

apparently there are conflicts with the java package.

terminal exit when launching sweet home 3d application.

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by javax.media.j3d.JoglPipeline (file:/usr
/lib/sweethome3d/java3d-1.6/j3dcore.jar) to ...