Index: trunk/src/org/openstreetmap/josm/gui/dialogs/relation/MemberTableModel.java
===================================================================
--- trunk/src/org/openstreetmap/josm/gui/dialogs/relation/MemberTableModel.java	(revision 7549)
+++ trunk/src/org/openstreetmap/josm/gui/dialogs/relation/MemberTableModel.java	(revision 7551)
@@ -205,4 +205,8 @@
     @Override
     public void setValueAt(Object value, int rowIndex, int columnIndex) {
+        // fix #10524 - IndexOutOfBoundsException: Index: 2, Size: 2
+        if (rowIndex >= members.size()) {
+            return;
+        }
         RelationMember member = members.get(rowIndex);
         RelationMember newMember = new RelationMember(value.toString(), member.getMember());
