You can clone with
HTTPS or Subversion.
When there's no HEAD handler, it uses the GET one but doesn't actually discard the response body, which it should. Most HTTP clients ignore it anyway so this should be safe to fix.
Sorry if i am wrong, since i don't have much experience with Flask's sourcecode, but couldn't the GET method not just discard the response body (for HEAD requests)?
That should not happen as Werkzeug is taking care of that when yielding to the WSGI server: https://github.com/mitsuhiko/werkzeug/blob/master/werkzeug/wrappers.py#L1025