New idea for hatch "crack" sealing...

I sealed the hairline cracks a few years ago, using GE clear silicone. Seems to have worked well, but honestly, it looks horrible when I open the hatch -- of course -- maybe it's just me noticing it -- and I did it when I was having trouble with my arm
Hatchback water leak | PriusChat.

But had to make a home roof repair where it appeared birds had pecked a hole and used a product called Through The Roof. It comes in caulking guns, but also comes as a liquid in a quart container with the thickness of -- say -- honey. Just brush it on. It was about $19 USD at my local hardware store. The maker (Sashco), is solid. And my repair seemed to work well and it was super easy to apply. Think if I had known about Through The Roof at the time, I would have used it, instead.Of course the SDS makes it sound...well....
Kris

https://www.sashco.com/products/through-the-roof/

https://www.sashco.com/wp-content/uploads/2022/02/TRF_SDS_brush-grade.pdf