Originally Posted by ESDSKeith
I think it is more flexing which straightens out. I've noticed this happens a few times. Mine is a new popup. Just level it out front to back and side to side before you bring down the door frame and put it all together. I've noticed this we hen it is all closed up and not leveled. Advice.....always open top couple inches before opening your door so you don't tear the weather strip on the top edge.
i learned that lesson the hard way. Ended up ripping the gasket right off the door. Will not make that mistake again. Now I unclip the top and lift the top up a bit in order to open the door. Not 2", but enough to clear the gasket. It would be too much of a pain to raise the roof everytime I wanted to put/get something from the pup.