I wiped the talcum powder off where I intended to glue it. I glued only a few sections at the front of the seal, where it goes around the door stop.
I believe the talcum makes it easier for the rubber to slide into the channels. It seems to be very stable in the channel. I can always glue it later, should it not stay in there.
Later, I treat rubber with glycerin, and thus wipe off the talcum on the outside.