I've always wiped my window seals around the caravan, as well as the thetford loo flap and the locker and entrance door with silicone lube thinking this was the right thing to do-never observed any ill effects BUT I read in one of the club mags-that silicone shouldn't contact acrylic windows as it can damage them. Never seen this nor can I find anything anywhere on the web to say it's particularly harmful to anything . Anyone else any thoughts?