st-sync.js wraps SyncManager, the native protocol. Three properties drove the
shape of it. It repeats the sync broadcast at 1Hz so a player powered on late
still joins, which means acting on every repeat would reload the video once a
second forever — on screen that reads as a stutter, not as a sync fault, so the
id dedupe is mandatory rather than an optimisation. The leader starts from its
OWN broadcast rather than at announce() time, or it runs ahead of the group by
the width of the network. And attachVideo refuses an element with no
setSyncParams instead of half-syncing it.
offline.html is the local fallback the host falls back to after three failed
loads. It names the server, keeps probing with capped backoff so a site full of
panels cannot storm a server that is coming back, and asks the HOST to restart
the player when it answers — never navigating itself, for the same reason the
player never reloads itself here.
The resolver now models multicast reach. All-BrightSign groups spread across
subnets no longer get native sync: each subnet would sync neatly within itself
while drifting from the others, and the dashboard would show a healthy group
throughout. The IP comparison is a heuristic so it is used in one direction
only — differing networks are evidence against, matching ones are never proof
for, and unknown addresses block nothing.
st-sync.js is served from its single source like the bridge, and the SD card
deliberately carries neither: the player pulls both from the server so a stale
copy on a card can never skew from the player using it.
948 pass.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Uaeo9MvzKoyXuN6ZsbhtkL
