3-finger tap only works after window drag

I am using Better Touch Tool version 3.552 on an iMac running macOS Big Sur, version 11.2.3. I set up a 3-finger tap to maximize a window. It only seems to work if I drag the window a little bit before doing the 3-finger tap. If I do not drag the window first, the tap does nothing. If I do an immediate second 3-finger tap, the window minimizes to the dock. I have no idea where this action is coming from. Anyway, shouldn't the tap maximize the window without having to drag it a little first?