$ /private/opt/local/bin/curl --http2 -vso /dev/null 'https://en.wikipedia.org/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cjquery.makeCollapsible.styles%7Cmediawiki.legacy.commonPrint%2Cshared%7Cmediawiki.page.gallery.styles%7Cmediawiki.skinning.interface%7Cmediawiki.toc.styles%7Cskins.vector.styles%7Cwikibase.client.init&only=styles&skin=vector'
*   Trying 2620:0:861:ed1a::1:443...
* TCP_NODELAY set
* Connected to en.wikipedia.org (2620:0:861:ed1a::1) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*   CAfile: /opt/local/share/curl/curl-ca-bundle.crt
  CApath: none
} [5 bytes data]
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
} [512 bytes data]
* TLSv1.3 (IN), TLS handshake, Server hello (2):
{ [102 bytes data]
* TLSv1.2 (IN), TLS handshake, Certificate (11):
{ [3608 bytes data]
* TLSv1.2 (IN), TLS handshake, Server key exchange (12):
{ [114 bytes data]
* TLSv1.2 (IN), TLS handshake, Server finished (14):
{ [4 bytes data]
* TLSv1.2 (OUT), TLS handshake, Client key exchange (16):
} [37 bytes data]
* TLSv1.2 (OUT), TLS change cipher, Change cipher spec (1):
} [1 bytes data]
* TLSv1.2 (OUT), TLS handshake, Finished (20):
} [16 bytes data]
* TLSv1.2 (IN), TLS handshake, Finished (20):
{ [16 bytes data]
* SSL connection using TLSv1.2 / ECDHE-ECDSA-CHACHA20-POLY1305
* ALPN, server accepted to use h2
* Server certificate:
*  subject: C=US; ST=California; L=San Francisco; O=Wikimedia Foundation, Inc.; CN=*.wikipedia.org
*  start date: Nov  8 10:47:06 2019 GMT
*  expire date: Nov 22 07:59:59 2020 GMT
*  subjectAltName: host "en.wikipedia.org" matched cert's "*.wikipedia.org"
*  issuer: C=BE; O=GlobalSign nv-sa; CN=GlobalSign ECC OV SSL CA 2018
*  SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
} [5 bytes data]
* Using Stream ID: 1 (easy handle 0x7fb209809c00)
} [5 bytes data]
> GET /w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cjquery.makeCollapsible.styles%7Cmediawiki.legacy.commonPrint%2Cshared%7Cmediawiki.page.gallery.styles%7Cmediawiki.skinning.interface%7Cmediawiki.toc.styles%7Cskins.vector.styles%7Cwikibase.client.init&only=styles&skin=vector HTTP/2
> Host: en.wikipedia.org
> user-agent: curl/7.67.0
> accept: */*
>
{ [5 bytes data]
* Connection state changed (MAX_CONCURRENT_STREAMS == 128)!
} [5 bytes data]
* http2 error: Invalid HTTP header field was received: frame type: 1, stream: 1, name: [proxy-connection], value: [keep-alive]
} [5 bytes data]
* HTTP/2 stream 0 was not closed cleanly: PROTOCOL_ERROR (err 1)
* stopped the pause stream!
* Connection #0 to host en.wikipedia.org left intact