WS connections dropped after enabling HTTP/2

[jscarty]

On a cro server I have set up. After enabling https in Cro::HTTP::Server. Chrome proves a failed: Connection closed before receiving a handshake response error from the dev console and firefox returns a vaguer _Firefox can’t establish a connection to the server at [websocket_address]/ws-connect. error from its dev console. I am sorry for the vague code example. I've found the below does not work

my Cro::Service $http = Cro::HTTP::Server.new(
    http => <1.1 2>,
    host => %*ENV<JSCARTY_HOST> ||
        die("Missing JSCARTY_HOST in environment"),
    port => %*ENV<JSCARTY_PORT> ||
        die("Missing JSCARTY_PORT in environment"),
    tls  => %(
        private-key-file => %*ENV<JSCARTY_TLS_KEY> ||
            %?RESOURCES<fake-tls/server-key.pem>,
        certificate-file => %*ENV<JSCARTY_TLS_CERT> ||
            %?RESOURCES<fake-tls/server-crt.pem>
    ),
    :$application,
    after => [
        Cro::HTTP::Log::File.new(logs => $*OUT, errors => $*ERR)
    ]
);

while the below does

my Cro::Service $http = Cro::HTTP::Server.new(
    http => <1.1>,
    host => %*ENV<JSCARTY_HOST> ||
        die("Missing JSCARTY_HOST in environment"),
    port => %*ENV<JSCARTY_PORT> ||
        die("Missing JSCARTY_PORT in environment"),
    :$application,
    after => [
        Cro::HTTP::Log::File.new(logs => $*OUT, errors => $*ERR)
    ]
);