@Override
      protected Condition<PsiFileSystemItem> getReferenceCompletionFilter() {
        return item -> {
          if (item instanceof PsiDirectory) return true;
          final VirtualFile virtualFile = PsiUtilCore.getVirtualFile(item);
          return virtualFile != null && acceptedExtension.equals(virtualFile.getExtension());
        };
      }
@Override
      protected Condition<PsiFileSystemItem> getReferenceCompletionFilter()