seems to miss level=3 setting
$ cat bin/ffmpeg/video/ffv1.avi
avi ffv1
$ cat bin/ffmpeg/video/ffv1.mkv
matroska ffv1
threads=8
context=1
slices=30
$ cat bin/ffmpeg/video/ffv1.mov
mov ffv1
#coder=0
context=1
g=1
level=3
threads=16
slices=16
slicecrc=1
#pass=2
$
not sure if we should modify our avi/mkv profikes or add new (may be with _v3 name) ones?