Tail number from flight number

Hi. Just joined flightaware defining myself as a geek plane spotter. It is often difficult to see the tail number because of obstructing jetways, angle of sunlight, etc. If I already know the tail number, the flightaware website lists all the recent flights for that specific plane, and I can thus find out details re that flight. However, if I know only the flight number, the website does not seem to provide a reverse trace back to the tail number. Can I identify tail numbers based only on flight numbers?

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Should be a sticky, but isn’t.