A rigger was helping a jumper get the twists out of a set of steering lines after landing. Once the twists were out, the rigger then tried to set the brakes but found the toggle locked to the risers by some sort of fraying material. At first, the rigger thought the steering line had frayed and was locking the toggle in place, but upon closer inspection she found the frayed material came from the elastic that holds excess brake line on the back of the riser. It had frayed to the point that the ends of the fraying piece wrapped around the riser and entangled around the guide ring and brake line. Fortunately, it did not do so while the canopy was opening, since it would likely have prevented the brake from releasing.
Jumpers should never ignore fraying or any other wear of components, especially when it is this extensive. This problem could have easily been prevented by snipping off the frayed portion of the elastic and sealing it with a hot knife (which any rigger likely has in their toolkit).