Jacks for the slide
I wish I had pics....but have seen many RVs in long-term sites with aux slide supports. When the RVs were prepped to move, most of the slides would not retract, two fell out when the aux supports were removed because the framing of the wall opening was messed up. And if a slide is lifted from the outer edge, it will leak.
If for a short-term stay, maybe they can be a benefit. But a stiff wind against one side can rock the RV. Although rocking slightly, it can be enough to seriously damage the slide and/or the opening.
The folks that are most successful in preventing damage when their RVs are on-site long-term, are those that retract their slides between trips to the "cabin".
Be cautious, my friends.