legoktm@mwmaint2002:~$ https_proxy=localhost:6501 curl 'https://meta.wikimedia.org/w/api.php?action=query&meta=siteinfo&format=json'
curl: (56) Received HTTP code 404 from proxy after CONNECT
legoktm@mwmaint2002:~$ https_proxy=localhost:6501 curl 'https://meta.wikimedia.org/w/api.php?action=query&meta=siteinfo&format=json' -vvv
*   Trying ::1...
* TCP_NODELAY set
* connect to ::1 port 6501 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to (nil) (127.0.0.1) port 6501 (#0)
* Establish HTTP proxy tunnel to meta.wikimedia.org:443
> CONNECT meta.wikimedia.org:443 HTTP/1.1
> Host: meta.wikimedia.org:443
> User-Agent: curl/7.52.1
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 404 Not Found
< date: Wed, 25 Aug 2021 16:11:47 GMT
< server: envoy
< connection: close
< content-length: 0
< 
* Received HTTP code 404 from proxy after CONNECT
* Curl_http_done: called premature == 0
* Closing connection 0
curl: (56) Received HTTP code 404 from proxy after CONNECT

legoktm@mwmaint2002:~$ http_proxy=localhost:6501 curl 'http://meta.wikimedia.org/w/api.php?action=query&meta=siteinfo&format=json' -vvv
*   Trying ::1...
* TCP_NODELAY set
* connect to ::1 port 6501 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to (nil) (127.0.0.1) port 6501 (#0)
> GET http://meta.wikimedia.org/w/api.php?action=query&meta=siteinfo&format=json HTTP/1.1
> Host: meta.wikimedia.org
> User-Agent: curl/7.52.1
> Accept: */*
> Proxy-Connection: Keep-Alive
> 
< HTTP/1.1 200 OK
< date: Wed, 25 Aug 2021 16:15:53 GMT
< server: envoy
< x-powered-by: PHP/7.2.34-18+0~20210223.60+debian10~1.gbpb21322+wmf1
< x-content-type-options: nosniff
< p3p: CP="See https://meta.wikimedia.org/wiki/Special:CentralAutoLogin/P3P for more info."
< x-frame-options: DENY
< content-disposition: inline; filename=api-result.json
< vary: Accept-Encoding,Treat-as-Untrusted,X-Forwarded-Proto,Cookie,Authorization
< cache-control: private, must-revalidate, max-age=0
< x-request-id: be88e580-5cd7-468a-bf6c-8cfa0ec1d8ae
< backend-timing: D=41035 t=1629908153146495
< content-type: application/json; charset=utf-8
< x-envoy-upstream-service-time: 44
< transfer-encoding: chunked