So this is one of the best bugs ever.
Yesterday me and @Freddiefrogs were at KPAO. There was one other aircraft:
Yep, he was floating.
As you can see, he taxiied and took-off as if he was on the ground.
KPAO, FF Server
Ipad Mini 2
Latest IF (non-beta)
Obviously this cannot be reproduced as this was another user. @Freddiefrogs reported the same though.