Index: trunk/src/org/openstreetmap/josm/tools/PlatformHookWindows.java
===================================================================
--- trunk/src/org/openstreetmap/josm/tools/PlatformHookWindows.java	(revision 4204)
+++ trunk/src/org/openstreetmap/josm/tools/PlatformHookWindows.java	(revision 4205)
@@ -4,4 +4,5 @@
 import static org.openstreetmap.josm.tools.I18n.tr;
 
+import java.awt.GraphicsEnvironment;
 import java.awt.event.KeyEvent;
 import java.io.File;
@@ -65,5 +66,6 @@
     public boolean canFullscreen()
     {
-        return true;
+        return GraphicsEnvironment.getLocalGraphicsEnvironment()
+        .getDefaultScreenDevice().isFullScreenSupported();
     }