Sentry: https://sentry.prod.mozaws.net/operations/socorro-new-prod/issues/16493731/

TypeError: 'str' object does not support item assignment
  File "raven/middleware.py", line 20, in common_exception_handling
    yield
  File "raven/middleware.py", line 100, in __call__
    iterable = self.application(environ, start_response)
  File "falcon/api.py", line 269, in __call__
    responder(req, resp, **params)
  File "markus/main.py", line 515, in _timer_decorator
    return fun(*args, **kwargs)
  File "antenna/breakpad_resource.py", line 290, in on_post
    raw_crash, dumps = self.extract_payload(req)
  File "antenna/breakpad_resource.py", line 234, in extract_payload
    raw_crash["payload"] = "json"

It probably means that raw_crash was not a dict. We should be validating the value.

willkg merged PR #789: "bug 1748256: handle when extra is not a dict value" in 211d893.

I deployed this to prod in bug #1757737. Marking as FIXED.