[isabelle-dev] NEWS: Improved GUI look-and-feel

[Makarius]

*** Isabelle/jEdit Prover IDE ***

* Improved GUI look-and-feel: the portable and scalable FlatLightLaf is
used by default on all platforms (appearance similar to IntelliJ IDEA).

This refers to Isabelle/efc58b56a6c7, it avoids various GUI problems on Linux
(broken GTK), Windows (bad button fonts), macOS (visual glitches).

Existing Isabelle installations (repository closes etc.) need to change
Utilities / Global Options / Appearance / Swing look & feel to "FlatLaf
Light", or "FlatLaf Dark" (presently untested).


	Makarius