Index: /trunk/src/org/openstreetmap/josm/gui/bbox/SlippyMapBBoxChooser.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/gui/bbox/SlippyMapBBoxChooser.java	(revision 12202)
+++ /trunk/src/org/openstreetmap/josm/gui/bbox/SlippyMapBBoxChooser.java	(revision 12203)
@@ -97,5 +97,5 @@
     private static CopyOnWriteArrayList<TileSourceProvider> providers = new CopyOnWriteArrayList<>();
     static {
-        addTileSourceProvider(new OsmTileSource.Mapnik());
+        addTileSourceProvider(() -> Arrays.<TileSource>asList(new OsmTileSource.Mapnik()));
         addTileSourceProvider(new TMSTileSourceProvider());
     }