Google Flights introduces price guarantee feature with refunds.

Google Flights has launched a pilot program in the U.S. for a new feature called "Price Guarantee" that predicts when the price of a flight might go up or down. If you see the "Price Guarantee" badge on a flight, that means the cost is likely the lowest it will go, so you can confidently book the flight without worrying it will get cheaper later. Google will keep monitoring the price and pay you back the difference through Google Pay if the price drops. The feature is only available for airlines that use "Book on Google" and is currently only available for flights departing from the U.S.