enable selection in the dialog item list

now the user can use the Ctrl and/or Shift key to select multiple items to be deleted

src/Mod/PartDesign/Gui/TaskDressUpParameters.cpp

@@ -197,7 +197,7 @@ void TaskDressUpParameters::setSelection(QListWidgetItem* current) {
         hideObject();
         // highlight all objects in the list
         DressUpView->highlightReferences(true);
-        // clear existing selections
+        // clear existing selection because only the current item is highlighted, not all selected ones to keep the overview
         Gui::Selection().clearSelection();
         // highligh the selected item
         Gui::Selection().addSelection(docName.c_str(), objName.c_str(), subName.c_str(), 0, 0, 0);