[iuyo5678]

Video browser CI can sample a previous frame after an MP4 seek, reporting red instead of blue in the encoder regression or white instead of red in the CLI/DSH regression. Main runs 40204484660 and 40306791830 show the affected assertions, and the original encoder failure was reproduced locally.

Every capture pixel check, including the route scan and dense late-overlay scan, now waits for both seek completion and presentation of the expected frame. Resolve the frame's presentation timestamp from the MP4 packet table and compare it with rVFC mediaTime; comparing directly to the requested seek time would reject valid long-lived static frames. Reuse verified repeated frames, move same-position seeks within the target frame, and reject unavailable metadata or out-of-range requests explicitly. Existing color, overlay, duration, recovery and export assertions remain active.

Retain MP4s, browser version, recording metadata, sampled pixels, screenshots and the Vitest JSON report. Evidence collection failures warn without replacing the test result, including optional CDP export failures. Metadata is saved before playback and updated after successful sampling so a playback failure still leaves useful evidence. Allow 30 minutes for the job's Chrome download, cold Rust build, video tests and native-dialog regressions.

Validation:

• 76 video unit tests and extension TypeScript compilation passed locally, including stale callbacks, both event orders, missing seek/presentation, media errors, invalid times, sparse MP4 timestamps and evidence failures.
• Full capture/encoder/export regression passed locally on Chrome for Testing 156.0.8078.47; the real encoder playback additionally exercises initial same-position seeks and repeated times.
• The updated revision passed the complete GitHub CI workflow, including video/native-dialog, frontend, Rust and Windows checks: https://github.com/Tencent/BrowserSkill/actions/runs/40447299295
• results.json and route MP4/JSON evidence were downloaded and verified from the updated Linux run. The reporter syntax is exercised by the actual workflow.
• An additional complete local browser run deliberately used a file as the evidence directory: MP4/JSON/screenshot writes warned and both functional regressions still passed.