Don’t know if it’s been mentioned before but as an owner of a convertible sports car and Motorhome….I’ve just been ‘feeding’ the rubber seals on the car to hopefully stop leaks in the future, and thought eh oh ….what about the seals around the windows etc on the Motorhome. Rubber is a natural product and dries out with time , hence seals cracking , going hard etc. So I’ve just gone round various seals on the Adria ….gummi phledge, is the product I use but there are various different ones out there. DONT USE silicone spray!!