Chiming in with 2020 Ram 1500 Longhorn built 08/2019. We finally got some real rain where I live (the desert) and noticed condensation and a weird humid feeling in my truck. The rear window corners are leaking after hose testing, but currently unsure about the 3rd brake light. The dealership told me that they usually just detach the brake light and use an RTV like sealant to fix that. Unfortunately, because of the lack of rain where I live, I didn't notice this until 46k miles so I'm on the hook for the repair.