Index: trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMTSLayerPanel.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMTSLayerPanel.java	(revision 13754)
+++ trunk/src/org/openstreetmap/josm/gui/preferences/imagery/AddWMTSLayerPanel.java	(revision 13755)
@@ -70,5 +70,9 @@
                 layerTable = new WMTSLayerSelection(layers);
                 layerTable.getTable().getSelectionModel().addListSelectionListener(lsl -> {
-                    name.setText(capabilities.getBaseUrl() + ": " + layerTable.getSelectedLayer().getUserTitle());
+                    if (layerTable.getSelectedLayer() != null) {
+                        name.setText(capabilities.getBaseUrl() + ": " + layerTable.getSelectedLayer().getUserTitle());
+                    } else {
+                        name.setText(capabilities.getBaseUrl() + ": ");
+                    }
                 });
                 layerPanel.removeAll();