Playing: https://example.org/video.ogg
[ffmpeg] https protocol not found, recompile FFmpeg with openssl, gnutls,
[ffmpeg] or securetransport enabled.
[ffmpeg] Protocol not found. Make sure ffmpeg/Libav is compiled with networking support.
Failed to open https://example.org/video.ogg
Incidentally, mpv appears not to have a man page. I was just curious how you might use it with SSL anyway.
After seeing this thread, I built a more recent version of mpv (with alienbob's more recent ffmpeg, which it requires) so it's possible the missing man page is a problem with my build.