Index: trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java	(revision 18246)
+++ trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java	(revision 18247)
@@ -123,4 +123,5 @@
         JButton btn = new JButton(action);
         btn.setPreferredSize(buttonDim);
+        btn.addPropertyChangeListener("enabled", propertyChangeEvent -> action.setEnabled(Boolean.TRUE.equals(propertyChangeEvent.getNewValue())));
         return btn;
     }