Cross the street in an American city, and few things will have a bigger impact on your chances of making it to the other side alive than the presence of a simple crosswalk, traffic light, or stop sign. The manual that sets the standard for such things is getting its first revision of the Vision Zero era — which could mean safer streets for pedestrians or simply better markings for robocars. Following an outpouring from advocates across the country, the Federal Highway Administration recently announced that it will extend the deadline for public comment to May 15 on the next edition of the Manual of Uniform Traffic Control Devices, which sets federal standards for the signs, markings and signals that help instruct road users on how to safely move through our communities.