[platform] UI scaling of a platform application in 2025

Due to a (now fixed) WorldWind/JOGL bug regarding mouse coordinate
translation I had to do a workaround with regard to UI scaling of a
platform application.

My solution was to have "-J-Dsun.java2d.uiScale=1
-J-Dprism.allowhidpi=false -J-Dflatlaf.uiScale=1" in the default_option and
scale the UI by myself depending on the value of --fontsize.

This was around 2018 or similar and has served me well, but now I read
something about that --fontsize is about to get deprecated/discouraged.

Any suggestions on what is best practice if I want a Swing+FlatLAF+JavaFX
application respect the OS default UI scaling, but with the possibility to
override?

/Patrik