WebSockets Fall Back not working


I’m working on an web app hosted at Portugal which is used in Spain. After some research, and contacting Vodafone Spain directly, I was assured by this company that websockets are not supported by their 3G/4G platform (it works in wifi). Vodafone is a mobile operator present in several countries. I found similar complains about Vodafone Netherlands, although the problem seems not to be present in Portugal.

To circumvent this i used DISABLE_WEBSOCKETS=1 and disable websockets.

However I was under the impression that there was a fall back system, where as if the websockets system was not working, the Ajax+JSON system fallback would take over. Strangely this did not happen and my app only started working over 3G/4G in Spain after I manually set the option for no websockets.

So, the questions: is there a fall-back system for when websockets aren’t available? Why didn’t it work?