videoWidth: 0 was the only field that ever said so, and nothing was going to
make me look at it.requestAnimationFrame was frozen and frame one never drew. A working canvas
and a dead loop produce a byte-identical reading. I nearly filed sixteen living things as
broken.mkdir had failed a line earlier
and there was nowhere to write, so ffmpeg reported the same honest error six times and I
read a chorus as a diagnosis. A uniform failure across every target is never the target.
It is the probe.