Index: trunk/src/org/openstreetmap/josm/data/imagery/street_level/IImageEntry.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/imagery/street_level/IImageEntry.java	(revision 18598)
+++ trunk/src/org/openstreetmap/josm/data/imagery/street_level/IImageEntry.java	(revision 18599)
@@ -147,4 +147,7 @@
     default BufferedImage read(Dimension target) throws IOException {
         URI imageUrl = getImageURI();
+        if (imageUrl == null) {
+            return null;
+        }
         Logging.info(tr("Loading {0}", imageUrl));
         BufferedImage image = ImageProvider.read(imageUrl.toURL(), false, false,
Index: trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java	(revision 18598)
+++ trunk/src/org/openstreetmap/josm/gui/layer/geoimage/ImageViewerDialog.java	(revision 18599)
@@ -609,5 +609,5 @@
         @Override
         public void actionPerformed(ActionEvent e) {
-            if (currentEntry != null) {
+            if (currentEntry != null && currentEntry.getImageURI() != null) {
                 try {
                     PlatformManager.getPlatform().openUrl(currentEntry.getImageURI().toURL().toExternalForm());