And here I see that JavaFx can shine. Few things still need to be done by Java runtime in my opinion, but Java if deployed, it is a great offline runtime which runs on the 3 major OSes and this is not a small deal. You can literally write once one UI and with no recompilation will run on all (desktop) platforms and if you consider JavaFxPorts, you can add Android to it.
So based on this I fixed some bugs with JavaFx types handling and use Java only (remove the Kotlin language) so it is easier to fix the code for non-Kotlin developers.
Code is here: