diff --git a/src/gui/qgsrelationeditorwidget.cpp b/src/gui/qgsrelationeditorwidget.cpp
index fb5155992f0..e99082d5fd4 100644
--- a/src/gui/qgsrelationeditorwidget.cpp
+++ b/src/gui/qgsrelationeditorwidget.cpp
@@ -64,7 +64,7 @@ class QgsFilteredSelectionManager : public QgsVectorLayerSelectionManager
       return mSelectedFeatureIds.count();
     }
 
-  public slots:
+  private slots:
 
     void onSelectionChanged( const QgsFeatureIds &selected, const QgsFeatureIds &deselected, bool clearAndSelect ) override
     {