I am on 3.7.13 and I am on WebUI v2.
I just now added a new macro button for $MI positioned near my macro button for $MD.
I can home Z to the max, then disable the steppers, and my LowRider drops. If I press my $MI button mid-drop, the LowRider stops dropping. It’s as responsive as when I press the “Home Z” button mid-drop, except that not only stops the drop but starts raising again.
At least on my test, the Z stepper is getting power when I do $MI.