docs: function should_add_international_option(properties)
  {
  	const { countries, international } = properties
  
  	// If this behaviour is explicitly set, then do as it says.
  	if (international !== undefined)
  	{
  		return international
  	}
  
  	// If `countries` is empty,
  	// then only "International" option is available, so add it.
  	if (countries.length === 0)
  	{
  		return true
  	}
  
  	// If `countries` is a single allowed country,
  	// then don't add the "International" option
  	// because it would make no sense.
  	if (countries.length === 1)
  	{
  		return false
  	}
  
  	// Show the "International" option by default
  	return true
  }