Safari 26: Video freezes on future frame after repeated backward seeks #7819

What version of Hls.js are you using?

1.6.15

What browser (including version) are you using?

Safari 26.4

What OS (including version) are you using?

MacOs 26.4

Test stream

No response

Configuration

{
  debug: true,
  enableWorker: true,
  lowLatencyMode: true,
  maxMaxBufferLength: 180,
  autoStartLoad: true,
  startLevel: 3,
  liveSyncDurationCount: 2,
  capLevelToPlayerSize: true,
  manifestLoadPolicy: {
    default: {
      maxTimeToFirstByteMs: 5000,
      maxLoadTimeMs: 5000,
      timeoutRetry: {
        maxNumRetry: 1,
        retryDelayMs: 0,
        maxRetryDelayMs: 0,
      },
      errorRetry: {
        maxNumRetry: 10,
        retryDelayMs: 1000,
        maxRetryDelayMs: 2000,
      },
    },
  },
  playlistLoadPolicy: {
    default: {
      maxTimeToFirstByteMs: 10000,
      maxLoadTimeMs: 5000,
      timeoutRetry: {
        maxNumRetry: 1,
        retryDelayMs: 0,
        maxRetryDelayMs: 0,
      },
      errorRetry: {
        maxNumRetry: 2,
        retryDelayMs: 1000,
        maxRetryDelayMs: 8000,
      },
    },
  },
  fragLoadPolicy: {
    default: {
      maxTimeToFirstByteMs: 5000,
      maxLoadTimeMs: 20000,
      timeoutRetry: {
        maxNumRetry: 1,
        retryDelayMs: 0,
        maxRetryDelayMs: 0,
      },
      errorRetry: {
        maxNumRetry: 4,
        retryDelayMs: 1000,
        maxRetryDelayMs: 2000,
      },
    },
  },
  maxBufferHole: 5,
};

Additional player setup steps

No response

Checklist

• The issue observed is not already reported by searching on Github under https://github.com/video-dev/hls.js/issues
• The issue occurs in the stable client (latest release) on https://hlsjs.video-dev.org/demo and not just on my page
• The issue occurs in the latest client (main branch) on https://hlsjs-dev.video-dev.org/demo and not just on my page
• The stream has correct Access-Control-Allow-Origin headers (CORS)
• There are no network errors such as 404s in the browser console when trying to play the stream

Steps to reproduce

1. Seek the video almost to the end (close to the end, but not completely)
2. Start rapidly seeking backward.
3. Stop seeking.
4. If the issue doesn't reproduce, repeat the steps.

Expected behaviour

Video don't stall after seeking

What actually happened?

When repeatedly seeking backward (e.g., in 10-second steps by holding down a key) in Safari 26.4 (macOS 26.4 Tahoe) — also reproducible in Safari 26.3 — the video freezes on a frame that is ahead of the current currentTime position. The currentTime continues to advance, and playback only resumes once the playback reaches that future frame.

This behavior is also reproducible with hls.js version 1.4.2.

In older versions of Safari, such as 18.6, seeking works correctly.

There are no errors in the logs from hls.js, nor from the browser.

The bug is intermittent but reproduces frequently.

video of bug: https://drive.google.com/file/d/1VwS8b3Vvwh3M7Urd2CvblHWkoM7NPUjZ/view?usp=sharing&t=41.704

video of bug on your testing env: https://drive.google.com/file/d/10x2d0rFjpgpPwWC0h6LnMighxQdn8W_h/view?usp=sharing

Console output

https://drive.google.com/file/d/1-Wp3RjoJOz_XTUacrus2JNuFGCfJ30Wn/view?usp=sharin

Chrome media internals output