Canopy causes cockpit fire

I think I can see how this would happen with the canopy open, and the
sunlight hitting it from "inside," reflecting off the canopy surface
onto the focal point of the almost-parabolic canopy. I'm still
holding onto the idea, though, that this can't happen in flight
because the sun can't hit the canopy from the inside. The thought of
an in-flight cockpit fire is really not comforting. Has anyone had
solar/canopy - related charring happen in flight?