Thanks. There are no fasteners... I'm guessing the fibreglass was glued down onto the timber roof. Did you use an outdoor silicone caulking or a regular bathroom type?
And looking at your picture, I'm thinking maybe I'd best try inserting a drip-edge all around (between the fibreglass and the wood frame). I think there might be enough of a gap to push a plastic strip in there with some gorilla glue or something on it (the fibreglass is wrapped over the edge all round, but does not hang down to shed the water)
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