diff --git a/avogadro/qtgui/jsonwidget.cpp b/avogadro/qtgui/jsonwidget.cpp
index 9d4302803d..b04e502ee4 100644
--- a/avogadro/qtgui/jsonwidget.cpp
+++ b/avogadro/qtgui/jsonwidget.cpp
@@ -209,26 +209,27 @@ void JsonWidget::buildOptionGui()
 
     // Add remaining keys at bottom.
     // look for "order" key to determine order
-    QStringList keys;
+    QMap<int, QString> keys;
+    int order = 0;
     for (QJsonObject::const_iterator it = userOptions.constBegin(),
                                      itEnd = userOptions.constEnd();
          it != itEnd; ++it) {
       if (it.value().isObject()) {
         QJsonObject obj = it.value().toObject();
         if (obj.contains("order") && obj.value("order").isDouble()) {
-          keys.insert(obj.value("order").toInt(), it.key());
-        } else {
-          keys.append(it.key());
+          order = obj.value("order").toInt();
+          keys.insert(order, it.key());
+        } else { // object doesn't contain "order"
+          keys.insert(order++, it.key());
         }
       } else {
-        keys.append(it.key());
+        keys.insert(order++, it.key());
       }
     }
 
     // now loop over keys and add them
-    for (const QString& key : keys) {
+    for (QString key : std::as_const(keys))
       addOptionRow(key, key, userOptions.take(key));
-    }
 
     // Make connections for standard options:
     if (auto* combo = qobject_cast<QComboBox*>(