more robust system init (again), in case the plugin is started without isabelle.Main;
--- a/src/Tools/jEdit/src/plugin.scala Wed Sep 30 14:37:21 2015 +0200
+++ b/src/Tools/jEdit/src/plugin.scala Wed Sep 30 14:49:39 2015 +0200
@@ -384,6 +384,7 @@
Debug.DISABLE_SEARCH_DIALOG_POOL = true
PIDE.plugin = this
+ Isabelle_System.init()
GUI.install_fonts()
PIDE.options.update(Options.init())