@Override
    public ExistingLibraryEditor getLibraryEditor(@NotNull Library library) {
      final LibraryTable table = library.getTable();
      if (table == null) return null;

      final LibraryTable.ModifiableModel model = myContext.getModifiableLibraryTable(table);
      if (model instanceof LibrariesModifiableModel) {
        return ((LibrariesModifiableModel)model).getLibraryEditor(library);
      }
      return null;
    }
@Override
    public ExistingLibraryEditor getLibraryEditor(@NotNull Library library)