Hi, Richard.
Thank you for your plugin!
I completely forgot tell you about a “little” detail – default WP rest headers is disbled, and it’s possible directly from my code: remove_filter( 'rest_pre_serve_request', 'rest_send_cors_headers' );
So there is no problem with my nginx configuration, and all headers are controled by nginx (production necessity).
I just asked you about the possibility to somehow disable sending headers in your plugin – be it a filter or an option in the admin panel.
Thank you.