3.7. might have some issues at the moment.
I did a checkout of 3.6.0, built and ran my app OK. Then I did 18.104.22.168 and again it ran OK.
But 3.7.0 not so good, I check the console in Chrome and I get "Failed to load resource: net::ERR_CONTENT_LENGTH_MISMATCH". My code looks like this:
void onAJAX_state(HttpRequest &request, HttpResponse &response)
JsonObjectStream* stream = new JsonObjectStream();
JsonObject& json = stream->getRoot();
json[_F("counter")] = counter;
. . .
I note that the code for the headers have been separated off into a new source file, but Im not sure what to invetigate next.