Flight Scan - Google Flights Tool

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Searches travel aggregate sites for the same Google Flight.Click on the icon and you will be presented with travel aggregate websites that you can toggle on or off, choosing whether to see a flight comparison from that site or not.

When you go to Google Flights, find a flight and click on that particular flight, a popup window at the top right of your browser will appear with a button that says "Compare". If you click this button, it will create a new tab for each site you have toggled ON and it will automatically search each site for the same flight you have up on Google Flights.