Index: /trunk/src/org/openstreetmap/josm/data/osm/OsmPrimitive.java
===================================================================
--- /trunk/src/org/openstreetmap/josm/data/osm/OsmPrimitive.java	(revision 11064)
+++ /trunk/src/org/openstreetmap/josm/data/osm/OsmPrimitive.java	(revision 11065)
@@ -665,6 +665,5 @@
             List<String> l = new LinkedList<>(Arrays.asList(
                 "source", "source_ref", "source:", "comment",
-                "converted_by", "watch", "watch:",
-                "description", "attribution"));
+                "watch", "watch:", "description", "attribution"));
             l.addAll(getDiscardableKeys());
             l.addAll(getWorkInProgressKeys());