Detect and recover from Panopto caption injection race - #1
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Panopto's viewer requests captions via fetch during boot. The custom SRT only applies if the userscript's fetch proxy is installed before that request fires; when Tampermonkey injects late (typically on fast cached loads), the original Panopto captions render while the banner still claims the custom SRT is active. Track whether the proxy actually intercepted a getCaptions request. If the transcript renders without interception, auto-reload up to twice (sessionStorage counter, reset on success or new upload). If it still fails, show a red failure banner instead of the misleading active one.
In Tampermonkey MV3 with Content Script API set to "UserScripts API Dynamic" (needed for reliable document-start injection), GM values are injected as a snapshot that updates asynchronously. A GM_setValue or GM_deleteValue followed immediately by a reload therefore boots with the previous value: reverting still shows the old SRT, and a fresh upload does not apply until a second manual reload (Tampermonkey issue #2123). Mirror the latest save/revert in sessionStorage, which is synchronous and survives same-tab reloads, and prefer it over the GM snapshot at boot. The mirror is dropped as soon as GM storage has caught up.
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Added a second commit (0bcd2fd): in Tampermonkey's 'UserScripts API Dynamic' mode (needed for reliable document-start injection), GM values are injected as a snapshot that lags one reload behind a fresh write, so Revert/Upload appeared to do nothing until a second manual reload. The latest save/revert is now mirrored in sessionStorage and preferred over a stale GM snapshot at boot; the mirror is dropped once GM storage catches up. |
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Well, the race condition is a guess - but this branch seems to work - will test and merge after. |
Long lecture titles squeezed the header so "Replace SRT" / "Revert to Default" / "Download" wrapped to multiple lines and bled into the video area. Hide the Panopto small logo to reclaim header width, shorten the button labels to one word with the full text in a hover tooltip, and force nowrap so the buttons can no longer wrap regardless of width.
Verified live: with the one-word buttons an extreme title no longer wraps them into the player, but it pushed them off the right edge of the viewport. Let .header-left shrink (min-width: 0) inside the flex header and ellipsize #deliveryTitle so the buttons always remain visible on a single line.
…s it
Buttons now default to their full labels ("Replace SRT", "Revert to
Default") with the logo visible. When the title actually truncates
(scrollWidth exceeds clientWidth), the script switches to one-word
labels and hides the logo; full labels stay available as hover
tooltips either way.
Expansion back uses a synchronous trial: restore full labels and logo,
force a reflow, and revert if the title truncates - nothing paints
mid-task so a failed trial is invisible. The title element is
shrink-to-fit (clientWidth always equals scrollWidth when it fits), so
truncation is the only reliable signal; a slack-based headroom check
can never fire. Trials are throttled to one per second because the
label swap itself retriggers the MutationObserver, and a resize
listener re-evaluates on window changes.
Verified live on the Auckland tenant: compact triggers on an inflated
title, stays stable while long, and expands back when the title fits.
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Problem
Custom SRT captions intermittently fail to apply: the viewer shows Panopto''s original ASR captions ("Uh, we''re going to...") while the script''s banner still claims "Custom SRT is active". Reloading sometimes fixes it; a cache-clearing reload reliably fixes it.
Root cause
The script works by proxying
window.fetchand answering the viewer''sDeliveryInfo.aspx+getCaptions=truerequest with the stored SRT. That only works if Tampermonkey injects the script before the viewer issues that request. On slow loads (cold cache, or Panopto''s current server slowness) the script wins the race; on fast cached loads it can lose, so the real captions load and the substitution silently never happens. The "Custom SRT is active" banner is driven purely by GM storage, so it lies when the race is lost.Verified live on the Auckland tenant: when injection wins, the transcript pane and docked CC overlay both show the custom SRT (946 cues vs the server''s 549); when it loses, the server captions render end-to-end.
Fix
interceptedCaptions).Unrelated observations from debugging, not addressed here: Panopto''s viewer itself is currently taking minutes to boot at times (reproduced with the script not injected), and the "Auto-play is disabled" toast is standard Chrome autoplay policy.