Fix Sources caption handling, retries, and thumbnails

[devhims]

Problem / Motivation

Videos without captions can show “YouTube is temporarily unavailable” and offer ineffective retries. Earlier proxy outages can mask confirmed absence. Retry controls lack dashboard styling, and thumbnails overflow their tiles.

What changed

Confirmed caption absence returns non-retryable CAPTIONS_UNAVAILABLE after successful, playable metadata checks. Bot challenges, rate limits, malformed responses, and missing requested languages retain their existing classifications.

Sources displays “No captions available”, including after restoration, and excludes confirmed absence from retries. Retries use styled buttons and skeletons with cancellation. Transcripts remain visible during ordinary refreshes. Thumbnails fill their 64-by-36-pixel tiles with a centered crop.

Library version 0.6.3 is published. The platform, processor container, and frame container now pin that release with updated lockfiles.

flowchart LR
  B["Before: confirmed empty captions"] --> E["Generic error or earlier outage"] --> R["Retry offered"]
  A["After: confirmed empty captions"] --> C["CAPTIONS_UNAVAILABLE"] --> U["No captions available"]
  classDef retained fill:#334155,color:#ffffff,stroke:#94a3b8;
  classDef replaced fill:#7f1d1d,color:#ffffff,stroke:#fca5a5;
  classDef added fill:#14532d,color:#ffffff,stroke:#86efac;
  class B,A retained;
  class E,R replaced;
  class C,U added;

Loading

Caption extraction is retained; confirmed absence replaces the generic error and retry path.

Tests

Platform build, 819 unit tests, 38 processor tests, and 16 frame-container tests passed. A regression test verifies terminal caption absence through the installed npm package. Frame extraction builds and storyboard bundle verification passed.

Earlier library, web, browser, documentation, skill bundle, and packed CommonJS/ESM checks passed. Docker builds remain unverified because the local daemon is unavailable.

Compatibility and deployment

Deploy platform and web together to activate the fixes and updated container dependencies. Confirmed caption absence gains a distinct API error code. No storage migration is required. Live verification of the supplied video remains pending deployment.

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Project	Deployment	Actions	Updated
video2ctx-web	Ready	Preview	Sep 27, 2026 8:55pm UTC