Added in 91d96dc8dd
The user can still turn this on via demuxer-lavf-o=extension_picky=1 if
they want to.
This causes quite a few problems with many HLS sources where the codecs
are not known at probe time for whatever reason. Youtube for instance
transports aac audio inside ".ts" extension urls which are disallowed by
this option.
As an aside, the FFmpeg test is also buggy and leaks a nested
connection for any playlist item that fails the extension check. mpv
catches this and prints "Leaking 1 nested connections (FFmpeg bug)" for
every HLS stream that has at least one stream that fails the extension
check.
b22a4da1df