This. The stiffener is designed to give the flap a tapered shape to allow lines to slide off of it. If the stiffener is broken, a loop of line can half-hitch around the flap and get stuck there, cinching up tight behind the broken stiffener. That gives the main canopy a violent spin, and if you cut it away, you'll still have it in-tow behind you. So now you have to dump your reserve into the streamer. People have died from this. RIP John Appleton.
Replace the stiffeners. ASAP!