Verified against ProPresenter 21.4: the legacy stage-display protocol
(ptl 610 — the only version PP21 accepts; newer values get 'out of
date') omits stage objects it predates, so a timecode field labeled LTC
never appears in any layout's frame list, and no timecode messages were
observed while idle. Fallback: an unknown uid streaming timecode-shaped
text (a fourth :FF group; not any configured timer's uuid) is bound as
LTC after two advancing samples, and that binding survives layout
refreshes. pp-timers-mock gains --ltc-unlisted to exercise the path.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
ProPresenter's HTTP API has no timecode route (verified: 21.4 returns
404), but its classic stage-display websocket still answers — so LTC now
comes from a stage layout field labeled "LTC": a zero-dependency RFC6455
client (stage-ws.js) authenticates (new stagePassword admin config),
resolves the LTC-labeled frame's uid from the layout list, and treats any
message carrying that uid as the timecode text. "Receiving" is a 2.5s
staleness heuristic; frozen or placeholder text reads as no-signal. The
HTTP probe stays authoritative when it ever answers (a 404 verdict is
retried once a minute), and the LTC card surfaces the reason when
timecode is unavailable (bad stage password, no LTC field). pp-timers-mock
grows a /stagedisplay websocket with --stage-pwd and --no-ltc-field to
exercise every path.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>