src/Tools/jEdit/src/jedit_lib.scala

--- a/src/Tools/jEdit/src/jedit_lib.scala	Thu Apr 14 20:47:44 2016 +0200
+++ b/src/Tools/jEdit/src/jedit_lib.scala	Thu Apr 14 22:55:53 2016 +0200
@@ -234,6 +234,12 @@
     }
   }
 
+  def invalidate(text_area: TextArea)
+  {
+    val visible_lines = text_area.getVisibleLines
+    if (visible_lines > 0) text_area.invalidateScreenLineRange(0, visible_lines)
+  }
+
 
   /* graphics range */