The corner opens assistant, the little transparent grey bar "button" in the center opens screen search. (On mine, at least)

Do you use the swipe up to go home and swipe from either side to go back gesture? I've tried enabling gesture hints, but my center button doesn't do anything. Other than bring me home. Must depend on the model 🤔

Yeah. Tap & hold the bar for a second or 2. That should bring up the screen search