How did William I die after his campaign at Mantes in 1087?

In July 1087, while campaigning at Mantes, William I either suffered a serious injury or fell fatally ill as the town burned. Following this event, he was taken to the priory of St. Gervais near Rouen, where he remained under the care of doctors for five weeks. He ultimately died there on September 9, 1087.1234

Would you like to know more about the succession arrangements he made while on his deathbed?