This was off for mpv CLI, but on for libmpv. The motivation behind this
was that it would be confusing for applications if libmpv continued
playback in a severely "degraded" way (without either audio or video),
and that it would be better to fail early.
In reality the behavior was just a confusing difference to mpv CLI, and
has confused actual users as well. Get rid of it.
Not bothering with a version bump, since this is so minor, and it's easy
to ensure compatibility in affected applications by just setting the
option explicitly.
(Also adding the missing next-release-marker in client-api-changes.rst.)
wm4
d690ee0959
