Slight tweak for performance

inabox.wpf/DynamicGrid/Editors/CodePopupEditor/CodePopupEditorControl.cs

@@ -266,8 +266,7 @@ public class CodePopupEditorControl : DynamicEditorControl<Guid, CodePopupEditor
     {
         var client = ClientFactory.CreateClient(_type);
         var columns = LookupFactory.DefineLookupColumns(Host.GetEditorType(), _type, ColumnName);
-        var cols = columns.ColumnNames();
-        foreach (var key in OtherColumns.Where(x => !cols.Contains(x.Key)))
+        foreach (var key in OtherColumns)
             columns.Add(key.Key);
         var sort = LookupFactory.DefineSort(_type);
         var filter = Filter.Create(_type, column).IsEqualTo(value);