static void markUnknownFileTypeAsPlainText(@NotNull VirtualFile file) {
    if (FileTypeRegistry.getInstance().isFileOfType(file, FileTypes.UNKNOWN)) {
      file.putUserData(KEY, Boolean.TRUE);
      FileContentUtilCore.reparseFiles(file);
    }
  }
static void markUnknownFileTypeAsPlainText(@NotNull VirtualFile file)