Apparently the concern at this phase is the front-rear timings bias of the deployments so it doesn't wreak havoc with car balance every time they're changed.
The wing adjustments are made hydraulically and the Ferrari is a more nearly race-ready configuration (it already was run once before at a Pirelli test, but that was a private affair). The green arrow points to an actuator arm, which is connected to the hydraulic motor inside the body work.
And since all they were looking at was timings, Mercedes didn't bother hiding the hydraulics.
Both 2025 cars used four element front wings so the active has one element less.
Guesstimates are that on 1000 bhp and with the wings closed they could top out better than 240 mph, so they better upgrade brakes in the off season.