fix #39571 , mesh 3d widgets ui fix

src/app/3d/qgsmesh3dsymbolwidget.cpp

@@ -70,6 +70,8 @@ QgsMesh3dSymbolWidget::QgsMesh3dSymbolWidget( QgsMeshLayer *meshLayer, QWidget *
            this, &QgsMesh3dSymbolWidget::changed );
 
   connect( mArrowsFixedSizeCheckBox, &QCheckBox::clicked, this, &QgsMesh3dSymbolWidget::changed );
+
+  connect( mGroupBoxTextureSettings, &QgsCollapsibleGroupBox::collapsedStateChanged, this,  &QgsMesh3dSymbolWidget::onTextureSettingsCollapseStateChanged );
 }
 
 void QgsMesh3dSymbolWidget::setSymbol( const QgsMesh3DSymbol *symbol )
@@ -242,6 +244,14 @@ void QgsMesh3dSymbolWidget::onColoringTypeChanged()
   mMeshSingleColorWidget->setVisible( mComboBoxTextureType->currentData()  == QgsMesh3DSymbol::SingleColor );
 }
 
+void QgsMesh3dSymbolWidget::onTextureSettingsCollapseStateChanged( bool collapsed )
+{
+  if ( !collapsed )
+  {
+    onColoringTypeChanged();
+  }
+}
+
 void QgsMesh3dSymbolWidget::setColorRampMinMax( double min, double max )
 {
   whileBlocking( mColorRampShaderMinEdit )->setText( QString::number( min ) );

src/app/3d/qgsmesh3dsymbolwidget.h

@@ -53,6 +53,7 @@ class QgsMesh3dSymbolWidget : public QWidget, private Ui::QgsMesh3dPropsWidget
 
     void onColorRampShaderMinMaxChanged();
     void onColoringTypeChanged();
+    void onTextureSettingsCollapseStateChanged( bool collapsed );
 
   private:
     double lineEditValue( const QLineEdit *lineEdit ) const;