Default was only [180p, 360p] simulcast fallback layers - a big
quality cliff straight to blocky 360p on minor network hiccups instead
of gracefully stepping down from the 1440p top layer. Added a 720p
middle rung. Also documented the likely real reason forcing video_codec:
vp9 broke calls (2026-07-28): LiveKit uses SVC for vp9/av1, not classic
simulcast, but buildPublishOptions() always builds simulcast-shaped
layers regardless of codec - needs a code fix before retrying vp9.
Thore Cimbal
7741180ae3