So if AWS ALB HTTP/2 listener -> HTTP/1.1 target downgrade was vulnerable, and the recommendation is to use HTTP/2 end to end... am I reading the AWS docs [1]

So if AWS ALB HTTP/2 listener -> HTTP/1.1 target downgrade was vulnerable, and the recommendation is to use HTTP/2 end to end... am I reading the AWS docs [1] correctly that ALB only supports HTTP/2 -> HTTP/1.1 downgrades, but not HTTP/1.1 -> HTTP/2 upgrades? In other words, using HTTP/2 as the target group protocol only works for HTTP/2 clients, and HTTP/1.1 clients will receive an error? [1] https://docs.aws.amazon.com/elasticloadbalancing/latest/application/load-balancer-target-groups.html#target-group-protocol-version https://docs.aws.amazon.com/elasticloadbalancing/latest/appl...