> By the way I have to ask, if I want this feature to be merged (this is my first PR)

Thank you for the PR and your contribution! Unless a PR is for a problem specific to a release, simply submit a PR against the master branch. If and when a core developer chooses to merge the PR, a decision will be made about whether to backport it and we have tools to do that semi-automatically. Be aware that, since we are all volunteers here, some areas in the code base do not receive a lot of attention and http.server is one of them. So don't be discouraged if your PR is not reviewed right away. A ping down the road may help.