$ ./save_page_as 2>&1 | grep Browser
  -b, --browser          Browser executable to be used (must be one of 'google-chrome', 'chromium-browser' or 'firefox'). Default = 'google-chrome'.
$ ./save_page_as example.com -b chromium-browser
INFO: The specified destination ('.') is a directory path, will save file inside it with the default name.
ERROR: Command 'chromium-browser' not found. Make sure it is installed, and in path.