Improvements to the progressive web app route-following experience: route-follow model and page updates, map-tile serving via the OS maps tile limiter, the route-follow service, and app version-check plumbing.
Route maps on walk pages were also sometimes failing to draw on slow connections, and in the app when installed on a phone. The request that fetches the route gave up after a few seconds, and once it gave up the map showed no route at all. It now waits up to 12 seconds, which is long enough for a slow mobile connection to answer.