Mine flip as the slide moves in or out.
They have done so on every unit we've owned.
Sometimes the entire seal doesn't flip just like in your photo.
I've read where some folks stick a piece of car molding on the slide wall to get them to flip.
A yardstick carefully slid up under the seal will flip it the rest of the way or I have a small diameter wooden dowel I carry that is the length of my widest slide (used to measure slide distance when arriving in a tight spot) and use that the few times it does not flip.
Mine typically don't flip for a few times shortly after seal treatment or right after polishing the side of the slide.
2016 Flagstaff 8529IKBS Diamond Package 5th Wheel-Goodyear Endurance Tires
2017 Ford F-Series SCREW 4x4 - Factory Puck B&W Companion
TST Tire Monitor w/Repeater - Sinemate 3500w Gen.
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