>> See >> https://github.com/apache/tomcat/blob/8.5.x/test/org/apache/coyote/http2/TestHttp2Section_5_1.java#L174
>From what I see in the test a STREAM_REFUSED is returned when a the maxConcurrentStream is set to one. Yet I'd like to understand how this value is changed internally. I think the only difference with my code is the call to the method doHttpUpgrade() which seems to send a GET for upgrade. Does this perform the actual upgrade of the settings? If this is the case where is it implemented?