>>5875530
wait no, -movflags is only for mp4 containers.

ffmpeg -i "12 - God Moving Over The Face Of The Waters.ogg" -i cover.jpg \
-map 0:a -c:a libopus -b:a 90k \
-map 1:v -c:v libvpx-vp9 -pix_fmt yuv420p -deadline best -crf 40 -loop 0 -r 1 \
-t 399 -y /tmp/Moby_-_GodMovingOverTheFaceOfTheWaters.webm

> ERROR: Maximum allowed video duration is 400 seconds.

Well shit, I had to add `-t 399` but I don't like it.