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Preview of Sync Audio Tabs

Sync Audio Tabs by FubarXS

Watch a show with audio from one language tab and subtitles from another, perfectly in sync.

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About this extension
Have you ever wanted to watch a video with audio in one language while using subtitles that are only available in another version of the same stream?

Sync Audio Tabs lets you synchronize two video players running in separate browser tabs. Use one tab as the Audio source and the other as the Subtitles source, then keep both videos synchronized to the same playback position.

How it works
  1. Open the same episode or video in two browser tabs, using the versions you need.
  2. Select one tab as Audio and the other as Subtitles.
  3. Start playback in either tab.
  4. The add-on automatically synchronizes the two video players.

The add-on also continuously corrects small timing differences between the two tabs to help keep audio and subtitles aligned during playback.

Features
  • Two-tab video synchronization — synchronize video playback between two browser tabs.
  • Audio + subtitles setup — use one tab for its audio and another for its subtitles.
  • Automatic play/pause synchronization — starting or pausing either video synchronizes the other tab.
  • Automatic drift correction — periodically corrects small differences in playback position.
  • Play Both / Pause Both — control both video players at the same time.
  • Fine synchronization controls — adjust either the Audio or Subtitles tab by +0.1 or −0.1 seconds.
  • Works with standard HTML5 video — the add-on interacts with the page's standard <video> element rather than downloading or modifying the media.

Example use case

Imagine a streaming service offers the same episode in two language versions:
  • Version A has the audio you want but no subtitles in your language.
  • Version B has the subtitles you want but different audio.

Open both versions in separate tabs and use Sync Audio Tabs to synchronize them. You can then listen to the audio from one tab while watching the subtitles from the other.

Privacy

Sync Audio Tabs does not send your data to any external server and does not have its own backend. It does not collect, store, or share personal information.

The add-on does not download or save video content and does not bypass DRM or other restrictions imposed by streaming services.

Compatibility

The add-on is designed for websites that use standard HTML5 <video> elements. It may not work on websites where the video is inaccessible, for example when it is deeply embedded in a cross-origin iframe or the website actively prevents access to the video element.

Sync Audio Tabs does not provide or add subtitles. It only synchronizes two already-playing video sources.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Optional permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
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Version
1.1
Size
32.9 KB
Last updated
4 days ago (Sep 7, 2026)
Related Categories
  • Tabs
License
All Rights Reserved
Version History
  • See all versions
Tags
  • youtube
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