Congratulations on forking!
Always remember that open-source is an author’s gift to the world, and the author doesn’t owe anything to anyone. Thus, if you need a feature that for whatever reason can’t or won’t go upstream, forking is just about the only viable option. Fingers crossed!
This is not merely open-source, but taking part in a huge package ecosystem in a foundational role in an XKCD 2347 type of way for HTTP requests.
Put your side project on your personal homepage and walk away - fine.
Make it central infrastructure - respond to participants or extend or cede maintainership.