diff --git a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
index ae4951b37c1..39af9203226 100644
--- a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
+++ b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
@@ -557,9 +557,9 @@ QgsCategorizedSymbolRendererWidget::QgsCategorizedSymbolRendererWidget( QgsVecto
   mExpressionWidget->registerExpressionContextGenerator( this );
 
   mMergeCategoriesAction = new QAction( tr( "Merge Categories" ), this );
-  connect( mMergeCategoriesAction, &QAction::triggered, this, &QgsCategorizedSymbolRendererWidget::mergeClicked );
+  connect( mMergeCategoriesAction, &QAction::triggered, this, &QgsCategorizedSymbolRendererWidget::mergeSelectedCategories );
   mUnmergeCategoriesAction = new QAction( tr( "Unmerge Categories" ), this );
-  connect( mUnmergeCategoriesAction, &QAction::triggered, this, &QgsCategorizedSymbolRendererWidget::unmerge );
+  connect( mUnmergeCategoriesAction, &QAction::triggered, this, &QgsCategorizedSymbolRendererWidget::unmergeSelectedCategories );
 }
 
 QgsCategorizedSymbolRendererWidget::~QgsCategorizedSymbolRendererWidget()
@@ -1163,7 +1163,7 @@ void QgsCategorizedSymbolRendererWidget::dataDefinedSizeLegend()
   }
 }
 
-void QgsCategorizedSymbolRendererWidget::mergeClicked()
+void QgsCategorizedSymbolRendererWidget::mergeSelectedCategories()
 {
   const QgsCategoryList &categories = mRenderer->categories();
 
@@ -1214,7 +1214,7 @@ void QgsCategorizedSymbolRendererWidget::mergeClicked()
   emit widgetChanged();
 }
 
-void QgsCategorizedSymbolRendererWidget::unmerge()
+void QgsCategorizedSymbolRendererWidget::unmergeSelectedCategories()
 {
   const QList<int> categoryIndexes = selectedCategories();
   if ( categoryIndexes.isEmpty() )
diff --git a/src/gui/symbology/qgscategorizedsymbolrendererwidget.h b/src/gui/symbology/qgscategorizedsymbolrendererwidget.h
index 5fd3120ab2b..0b926993732 100644
--- a/src/gui/symbology/qgscategorizedsymbolrendererwidget.h
+++ b/src/gui/symbology/qgscategorizedsymbolrendererwidget.h
@@ -153,8 +153,21 @@ class GUI_EXPORT QgsCategorizedSymbolRendererWidget : public QgsRendererWidget,
     void cleanUpSymbolSelector( QgsPanelWidget *container );
     void updateSymbolsFromWidget();
     void dataDefinedSizeLegend();
-    void mergeClicked();
-    void unmerge();
+
+    /**
+     * Merges all selected categories into a single multi-value category.
+     *
+     * \see unmergeSelectedCategories()
+     */
+    void mergeSelectedCategories();
+
+    /**
+     * Unmerges all selected multi-value categories into a individual value categories.
+     *
+     * \see mergeSelectedCategories()
+     */
+    void unmergeSelectedCategories();
+
     void showContextMenu( QPoint p );
 
   protected:
diff --git a/tests/src/gui/testqgscategorizedrendererwidget.cpp b/tests/src/gui/testqgscategorizedrendererwidget.cpp
index bdb10f0e113..2173e9f5833 100644
--- a/tests/src/gui/testqgscategorizedrendererwidget.cpp
+++ b/tests/src/gui/testqgscategorizedrendererwidget.cpp
@@ -151,17 +151,17 @@ void TestQgsCategorizedRendererWidget::merge()
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 5 ).value().toString(), QString() );
 
   // no selection, should have no effect
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 6 );
 
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 1, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
   // one selection, should have no effect
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 6 );
 
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 3, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 4, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 4 );
 
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 0 ).value().toString(), QStringLiteral( "a" ) );
@@ -179,7 +179,7 @@ void TestQgsCategorizedRendererWidget::merge()
   // selection should always "merge into" first selected item
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 2, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 0, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 3 );
 
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 0 ).value().toList().at( 0 ).toString(), QStringLiteral( "b" ) );
@@ -198,7 +198,7 @@ void TestQgsCategorizedRendererWidget::merge()
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 1, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
   //"" entry should be ignored
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 2, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
 
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 2 );
 
@@ -214,15 +214,15 @@ void TestQgsCategorizedRendererWidget::merge()
 
   widget->viewCategories->selectionModel()->clearSelection();
   // unmerge
-  widget->unmerge();
+  widget->unmergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 2 );
   // not a list
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 1, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
-  widget->unmerge();
+  widget->unmergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 2 );
   // list
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 0, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
-  widget->unmerge();
+  widget->unmergeSelectedCategories();
 
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 6 );
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 0 ).value().toString(), QStringLiteral( "b" ) );
@@ -240,15 +240,15 @@ void TestQgsCategorizedRendererWidget::merge()
 
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 2, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 3, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 3, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 4, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->mergeClicked();
+  widget->mergeSelectedCategories();
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 0, 0 ), QItemSelectionModel::ClearAndSelect | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 1, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 2, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
   widget->viewCategories->selectionModel()->select( widget->viewCategories->model()->index( 3, 0 ), QItemSelectionModel::Select | QItemSelectionModel::Rows );
-  widget->unmerge();
+  widget->unmergeSelectedCategories();
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().count(), 6 );
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 0 ).value().toString(), QStringLiteral( "b" ) );
   QCOMPARE( static_cast< QgsCategorizedSymbolRenderer * >( widget->renderer() )->categories().at( 1 ).value().toString(), QString() );