Ugly UI

...

when GTK+ Look and Feel

...

is active

Java 11+ uses Gnome 3 Libraries by default for rendering. Causing ugly UI rendering on GTK+ Look and Feel.

You might also want to improve the font rendering on Java 11

Solution:

Solution:

1. Use FlatLAF (which is enabled by default) or
2. add
3. If you would like to keep using Gnome 3, then you need to change the Look and Feel, Nimbus or Darcula are looking great,
4. Add -J-Djdk.gtk.version=2.2 to your command line or to your (netbeans.cfg) if you want to use the GTK LAF