SpecularDataImportWidget: unique connection

GUI/View/Import/SpecularDataImportWidget.cpp

@@ -205,7 +205,7 @@ void SpecularDataImportWidget::onFormatSelectionChanged()
     updatePropertiesEdits();
     updatePreview();
     connect(m_loader, &AbstractDataLoader::importSettingsChanged, this,
-            &SpecularDataImportWidget::onPropertiesChanged);
+            &SpecularDataImportWidget::onPropertiesChanged, Qt::UniqueConnection);
 }
 
 void SpecularDataImportWidget::updatePreview()
@@ -324,6 +324,7 @@ void SpecularDataImportWidget::onCreateNewFormatButton()
 
 void SpecularDataImportWidget::onPropertiesChanged()
 {
+    qInfo() << "Import : onPropertiesChanged";
     m_loader->applyImportSettings(); // #baimport: may be duplicate
     QApplication::setOverrideCursor(Qt::WaitCursor);
     m_loader->processContents();