diff -r 3df1b6a5837c -r a870098fc27e src/Tools/jEdit/src/text_overview.scala
--- a/src/Tools/jEdit/src/text_overview.scala	Tue Nov 24 22:50:03 2015 +0100
+++ b/src/Tools/jEdit/src/text_overview.scala	Tue Nov 24 23:17:03 2015 +0100
@@ -25,7 +25,7 @@
 
   private def lines(): Int = buffer.getLineCount max text_area.getVisibleLines
 
-  private val WIDTH = 10
+  private val WIDTH = text_area.getPainter.getFontMetrics.stringWidth("A") max 10
   private val HEIGHT = 4
 
   setPreferredSize(new Dimension(WIDTH, 0))