From the several images I have seen of the type of aircraft involved, some don't appear to have any ventilation panels set into the single piece canopies.
However, how such panels, when open, would in practice assist in "evacuating" smoke/gas from the cockpit is open to debate. The pressure differential may act to "draw" more smoke/gas from the engine area at a rate faster than that which is being expelled?
Also raises a question of on board fire extinguishers. . . .and so on . . . .