I'm not sure, why should someone rely on long polling alone. Default fallback mechanism is websockets (supported on iOS), long polling (not supported anymore, o

I'm not sure, why should someone rely on long polling alone. Default fallback mechanism is websockets (supported on iOS), long polling (not supported anymore, obviously) and then follows separate ajax calls. It is not uncommon that something in this sequence would break by design, unsupportedness or bad data connection, so fallback should be used.