These were common on our first slideouts when they were pulled out by hand.
My first rv trailer with a powered electric/gear slideout was a 1984 5er. It came with two carpet covered 2x3 boards cut to the proper length to keep the slideout in. The slideout never moved when in while going down the road so after a time they stayed in the storage bin.
Our 2nd rv with a slide was a '96 electric/hyd unit. The trailer mfg cheaped out and didn't add a double acting control valve that would hold the slide in.
I added two heavy slam latches on the two slideout tubes to keep the slideout in.
Our present slideouts are both electric/gear and will not move/creep once out or in.
If your slideout creeps out easily I wouldn't use a adjustable shower curtain rod as a slideout is heavy while on twisty winding roads.
What ever you use keep a close watch while going down the road.