Gnome or KDE? Because I would strongly recommend using GTK4 for gnome and QT for KDE. Otherwise the app might never really look good enough.
Discussion
trying hard to avoid native toolkits. I want something what looks same everywhere. even if it sucks.
I kidnof think that people already gave up on native look. since electron ...
Not a good idea. I see tons of those apps. They never look good enough for each of the user groups. You end up conquering no user.
javafx use native look. it's matter of styling. like a web app.
but true.
i have different problems now the UI frankly.