Have you removed the screen and checked the frame joints in that area? I went back to your exterior pic and enlarged it. Looks like a possibility for a leak?
Or tape plastic over the flat edge inboard of the screws and cover the glass / screen area and see if it dries up. Might help narrow down the source.
Or tape plastic over the flat edge inboard of the screws and cover the glass / screen area and see if it dries up. Might help narrow down the source.
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