Index: trunk/src/org/openstreetmap/josm/data/gpx/GpxExtension.java
===================================================================
--- trunk/src/org/openstreetmap/josm/data/gpx/GpxExtension.java	(revision 15628)
+++ trunk/src/org/openstreetmap/josm/data/gpx/GpxExtension.java	(revision 15629)
@@ -234,5 +234,5 @@
     @Override
     public int hashCode() {
-        return Objects.hash(prefix, key, value, attr, parent, visible, super.hashCode());
+        return Objects.hash(prefix, key, value, attr, visible, super.hashCode());
     }
 
@@ -270,9 +270,4 @@
         } else if (!attr.equals(other.attr))
             return false;
-        if (parent == null) {
-            if (other.parent != null)
-                return false;
-        } else if (!parent.equals(other.parent))
-            return false;
         return true;
     }
Index: trunk/test/unit/org/openstreetmap/josm/data/gpx/GpxExtensionTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/data/gpx/GpxExtensionTest.java	(revision 15628)
+++ trunk/test/unit/org/openstreetmap/josm/data/gpx/GpxExtensionTest.java	(revision 15629)
@@ -39,5 +39,5 @@
         EqualsVerifier.forClass(GpxExtension.class).usingGetClass()
         .suppress(Warning.NONFINAL_FIELDS)
-        .withIgnoredFields("qualifiedName")
+        .withIgnoredFields("qualifiedName", "parent")
         .withPrefabValues(GpxExtensionCollection.class, new GpxExtensionCollection(), col)
         .verify();