The same idea in different form. White sees that his pawn on g3 is one move from attacking the enemy queen on h5. The move would be a lot more interesting if it also attacked something else. There is not yet a working fork because on f5 Black has a pawn—an unsuitable target. So again White asks whether he has anything he can use to capture the pawn and cause it to be upgraded to a target that will work. He finds one option for the purpose: Bxf5+. Black’s only legal reply is KxB, leaving his king and queen in position to be forked with g3-g4. Of course a pawn fork of the queen only works if the pawn has protection, and it does—from the pawn on h3.
Again, another way to have seen this would have been to examine every check. White has two: Rb6, which Black escapes easily, and Bxf5, which looks improbable but requires Black to move his king to recapture. You imagine this response, see the telltale resulting position of Black’s king and queen, and take it from there.