Video Timeline Marker for YouTube & Twitch by ErttyOuO

For video editors, highlight creators, stream recap editors, and anyone who needs to keep track of timestamps in videos.

When watching YouTube or Twitch, you’ll often come across moments you want to clip, revisit, organize, or add notes to later. Video Timeline Marker lets you save those moments without opening a separate note-taking app or manually copying timestamps. Simply click the 🔖 marker button on the playback page to instantly save the current timestamp along with the video information.

One-Click Marking

A marker is created the moment you click the marker button—there’s no need to press Save again.

Once the marker panel opens, the cursor automatically moves to the notes field so you can start typing immediately. Your notes are automatically saved after you stop typing.

Fast Keyboard Workflow

Enter: Confirm and close the marker panel
Shift + Enter: Insert a new line in your note
+: Move the current marker forward by 5 seconds
-: Move the current marker backward by 5 seconds

The + / - shortcuts continue to work even while you’re typing in the notes field.

When using a Chinese or Japanese IME, Enter will not be intercepted while text composition is in progress.

For Twitch VODs, the extension uses the player’s actual playback time. For Twitch Live streams, it calibrates timestamps using the live elapsed time shown on the page together with relative changes in the player position, and displays the corresponding calibration status.

Timeline List

Markers from the same video or live stream are automatically sorted from earliest to latest according to the media’s own timeline.

Even if you jump back and forth through a video and create markers out of order, you’ll still end up with a clean, chronological timestamp list that’s easy to hand off for editing.

TXT Export Support

• Export a single marker
• Export all markers from a single video or live stream
• Select multiple videos for batch export
• Export everything

Each video or live stream is exported as its own TXT file, so markers from different videos are never mixed together.

Privacy First

All markers and notes are stored locally in Firefox using browser.storage.local.

This extension does not use analytics, telemetry, advertising SDKs, or a developer-operated backend, and your markers and notes are never uploaded to a server.

Why These Permissions Are Needed

Storage: Saves markers and notes locally.

Downloads: Used only when you explicitly export TXT files.

YouTube / Twitch site access: Used to read the information required from playback pages, including the title, channel/streamer name, URL, and current playback time, and to add the marker interface to the page.

Current Limitations

• The dedicated YouTube Shorts interface is not supported.
• Twitch Live uses page-based live-time calibration, which differs from the direct player-time method used for VODs.
• Twitch OAuth / Helix API integration is not currently used to automatically match Live markers with the corresponding VOD after a stream ends.
• This extension is independently developed and is not officially affiliated with YouTube, Google, or Twitch.