I have the following in app.yaml:

- url: /gae_mini_profiler/static
  static_dir: gae_mini_profiler/static

- url: /gae_mini_profiler/.*
  script: gae_mini_profiler/main.py

- url: .*
  script: main.py

and the following in gae_mini_profiler/main.py:

def main():
    logging.critical("gae_mini_profiler request!")
    run_wsgi_app(application)

However, when I fire requests to, say, /gae_mini_profiler/request?request=ABC, and repeatedly reload the page, sometimes I will get the proper response (as well as a "gae_mini_profiler request!" log entry, and sometimes I get a blank response and nothing in the App Engine logs other than a 200 with an empty response body.

This is completely reproducible, only happens in the live environment, and I'd say ~50% of the refreshes work while 50% do not.

This only happens in production. Any ideas?