diff --git a/src/gui/qgsmaskingwidget.cpp b/src/gui/qgsmaskingwidget.cpp
index 93978051807c..4b5806eea2db 100644
--- a/src/gui/qgsmaskingwidget.cpp
+++ b/src/gui/qgsmaskingwidget.cpp
@@ -37,6 +37,9 @@ QgsMaskingWidget::QgsMaskingWidget( QWidget *parent ) :
   QgsPanelWidget( parent )
 {
   setupUi( this );
+
+  connect( mMaskTargetsWidget, &QgsSymbolLayerSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
+  connect( mMaskSourcesWidget, &QgsMaskSourceSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
 }
 
 void QgsMaskingWidget::onSelectionChanged()
@@ -58,29 +61,6 @@ void QgsMaskingWidget::onSelectionChanged()
   emit widgetChanged();
 }
 
-void QgsMaskingWidget::showEvent( QShowEvent *event )
-{
-  Q_UNUSED( event );
-
-  // populate is quite long, so we delay it when the widget is first shown
-  if ( mMustPopulate )
-  {
-    disconnect( mMaskTargetsWidget, &QgsSymbolLayerSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
-    disconnect( mMaskSourcesWidget, &QgsMaskSourceSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
-
-    mMustPopulate = false;
-    populate();
-
-    connect( mMaskTargetsWidget, &QgsSymbolLayerSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
-    connect( mMaskSourcesWidget, &QgsMaskSourceSelectionWidget::changed, this, &QgsMaskingWidget::onSelectionChanged );
-
-    onSelectionChanged();
-  }
-}
-
-
-
-
 /**
  * Symbol layer masks collector. It is an enhanced version of QgsVectorLayerUtils::symbolLayerMasks.
  * Indeed, we need here to know both mask sources and targets for all masks
@@ -107,15 +87,15 @@ QList<QPair<QString, QList<QgsSymbolLayerReference>>> symbolLayerMasks( const Qg
 
 void QgsMaskingWidget::setLayer( QgsVectorLayer *layer )
 {
-  if ( mLayer != layer )
-  {
-    mLayer = layer;
-    mMustPopulate = true;
-  }
+  mLayer = layer;
+  populate();
 }
 
 void QgsMaskingWidget::populate()
 {
+  mMaskSourcesWidget->blockSignals( true );
+  mMaskTargetsWidget->blockSignals( true );
+
   mMaskSourcesWidget->update();
   mMaskTargetsWidget->setLayer( mLayer );
 
@@ -175,6 +155,9 @@ void QgsMaskingWidget::populate()
 
   mMaskSourcesWidget->setSelection( maskSources );
   mMaskTargetsWidget->setSelection( maskedSymbolLayers );
+
+  mMaskSourcesWidget->blockSignals( false );
+  mMaskTargetsWidget->blockSignals( false );
 }
 
 void QgsMaskingWidget::apply()
@@ -276,11 +259,6 @@ void QgsMaskingWidget::apply()
   }
 }
 
-bool QgsMaskingWidget::hasBeenPopulated()
-{
-  return !mMustPopulate;
-}
-
 SymbolLayerVisitor::SymbolLayerVisitor( SymbolLayerVisitor::SymbolLayerCallback callback ) :
   mCallback( callback )
 {}
diff --git a/src/gui/qgsmaskingwidget.h b/src/gui/qgsmaskingwidget.h
index 784aea508c5d..84b7105ca634 100644
--- a/src/gui/qgsmaskingwidget.h
+++ b/src/gui/qgsmaskingwidget.h
@@ -50,13 +50,6 @@ class GUI_EXPORT QgsMaskingWidget: public QgsPanelWidget, private Ui::QgsMasking
     //! Applies the changes
     void apply();
 
-    //! Widget has been populated or not
-    bool hasBeenPopulated();
-
-  protected:
-
-    void showEvent( QShowEvent * ) override;
-
   private slots:
 
     /**
@@ -70,7 +63,7 @@ class GUI_EXPORT QgsMaskingWidget: public QgsPanelWidget, private Ui::QgsMasking
     void populate();
 
     QPointer<QgsMessageBarItem> mMessageBarItem;
-    bool mMustPopulate = false;
+
     friend class TestQgsMaskingWidget;
 };
 
diff --git a/src/gui/vector/qgsvectorlayerproperties.cpp b/src/gui/vector/qgsvectorlayerproperties.cpp
index 04b804fae73e..fd37d889f684 100644
--- a/src/gui/vector/qgsvectorlayerproperties.cpp
+++ b/src/gui/vector/qgsvectorlayerproperties.cpp
@@ -738,7 +738,7 @@ void QgsVectorLayerProperties::apply()
   mMetadataFilled = false;
 
   // save masking settings
-  if ( mMaskingWidget && mMaskingWidget->hasBeenPopulated() )
+  if ( mMaskingWidget )
     mMaskingWidget->apply();
 
   //