1. Getting Started
🖥️ Chrome / Edge Extension
- Install the extension from the Chrome Web Store.
- Open any YouTube watch page.
- Click the Video Study Hub icon in the toolbar to open the sidebar.
- The sidebar auto-detects the current video and shows its title.
📱 iPad / macOS App
- Download from the App Store.
- Choose Import Local Video for a file on your device, or choose Web Service to open a web video service.
- The selected video opens with playback controls, bookmarks, loop tools, and notes in the study workspace.
- Optionally sign in to Cloud Sync to receive your latest bookmarks automatically.
2. Interface Overview
Extension Sidebar Tabs
| Tab | Description |
|---|---|
| Player | Playback controls, A-B Loop, and Markers — your main workspace. |
| Library | All saved videos and sessions in one list. |
| Settings ⚙️ | Cloud account, snapshot management, and preferences. |
Status Indicators
- 🟢 Green — Connected to the current video.
- ⚫ Grey — Standby, no video detected.
- 🟡 Amber title — Controlled video is in a hidden/background tab.
- 🔵 Blue title — Pop-out window mode active.
3. Playback Controls
| Button | Action |
|---|---|
| ⏮ Restart | Jump to the beginning |
| ⏪ −10s | Rewind 10 seconds |
| ⏯ Play/Pause | Toggle playback |
| ⏩ +10s | Fast-forward 10 seconds |
Playback Speed
Drag the speed slider (0.25x – 3.0x) or use preset buttons: 0.5x 1.0x 1.5x 2.0x.
Keyboard: Shift+, to decrease and Shift+. to increase by 0.05x.
4. A-B Loop Practice
Repeat any video segment — perfect for music practice, language shadowing, or focused study.
Steps
- Set Point A — Play to your target position and press [ or click "Set A".
- Set Point B — Continue playing and press ] or click "Set B".
- Enable Loop — Press Shift+] to toggle the loop.
- Jump to A — Press Shift+[ to return instantly to the start.
- Fine-tune — Edit timestamps directly in the input fields (
mm:ss). - Clear — Click the clear button to reset both points.
5. Timeline Markers
Drop timestamped markers anywhere on a video and jump back with one click.
| Action | How |
|---|---|
| Add a marker | Press A or click "+ Add Marker" |
| Restart segment | Press R |
| Follow playback | Toggle "Follow" switch or press S |
| Browse markers | ↑ / ↓ |
Marker Groups
Create separate groups for different learning contexts (e.g. Default, Vocabulary, Grammar). Each group is completely independent.
Import / Export
Back up all markers to a JSON file via the export icon. Restore anytime by importing the same file.
6. Library & Playlists
Saving a Video
Click the ❤️ icon to save the current video with its A-B points and all markers to your Library.
| Feature | Description |
|---|---|
| Batch management | Enter edit mode to bulk-delete or move videos between groups. |
| Index sorting | Type an index number to precisely reorder videos in a group. |
| Clone Session | Duplicate the current session for an independent variation of the same video. |
| Set as Default | This session auto-loads next time you open the video. |
Group Playlist Mode
- Go to Library, select a group, and click ▶ Play Group.
- The player enters Playlist Mode with a green banner and Prev/Next buttons.
- Videos play sequentially and transition automatically.
- Use Alt+[ / Alt+] to switch manually.
7. ☁️ Cloud Sync
Sign In
- In the extension: go to Settings ⚙️ → Cloud Sync.
- Enter your email and click "Send 6-Digit Code".
- Enter the code and click "Verify" to complete sign-in.
- Use the same credentials in the iPad / Mac App to link all platforms.
Automatic Sync Flow
| Trigger | Action |
|---|---|
| App launches / Sidebar opens | Downloads latest cloud data and smart-merges with local. |
| Switching back to the iPad/Mac App | Automatically merges again (ScenePhase foreground trigger). |
| 5 s after your last change | Silently uploads the snapshot (debounced). |
Manual Sync (Extension)
- Go to Settings → Cloud Sync → Cloud Snapshots.
- Click ⤓ Restore (blue) to overwrite local with the cloud snapshot.
- Or click ⇄ Merge (purple) to intelligently combine both (recommended).
- Quickest option: close and reopen the sidebar — it syncs on open.
8. iPad / Mac App Guide
| Orientation | Layout |
|---|---|
| Landscape | video player on the left, controls on the right. Drag the divider to resize. |
| Portrait | Player on top, controls at the bottom. Drag the handle bar to resize. |
Key Actions
- Home — Return to the neutral video source picker.
- Import Local Video — Open a video file from your device.
- Web Service — Choose a web video website or enter a video URL. This is not limited to a single service.
- ❤️ Save — Save the video with all markers and A-B settings.
- Library button — Browse all saved videos and playlists.
- Cloud Sync panel — Manage your cloud account and sync state.
- ? Help — View keyboard shortcuts and sync mechanism summary.
9. Keyboard Shortcuts
Playback
| Shortcut | Action |
|---|---|
| Space / K | Play / Pause |
| J | Rewind 10s |
| L | Forward 10s |
| ← / → | Seek ±5s |
| , / . | Frame Back / Forward (±0.05s) |
| 0–9 | Jump to 0%–90% |
Speed
| Shortcut | Action |
|---|---|
| Shift+, | Speed −0.05× |
| Shift+. | Speed +0.05× |
A-B Loop
| Shortcut | Action |
|---|---|
| [ | Set Point A |
| ] | Set Point B |
| Shift+[ | Jump to Point A |
| Shift+] | Toggle A-B Loop |
Markers & Navigation
| Shortcut | Action |
|---|---|
| A | Add Marker at current time |
| S | Toggle Follow Playback |
| R | Restart current segment |
| ↑ / ↓ | Jump to previous / next marker |
| Alt+[ | Previous video (Playlist mode) |
| Alt+] | Next video (Playlist mode) |
Global Shortcuts (Any Page)
| Shortcut | Action |
|---|---|
| Alt+Shift+P | Play / Pause |
| Alt+Shift+A | Add Marker |
| Alt+Shift+R | Restart Segment |
10. FAQ
🔸 The sidebar can't detect the video?
Make sure you're on a YouTube watch page (URL contains watch?v=). Click 🪄 Auto Detect to trigger detection manually.
🔸 Controls stopped working after switching tabs?
Extension: click anywhere on the YouTube video tab, then use 🪄 Relink. iPad / Mac: return Home and reopen the local video or Web Service entry if needed.
🔸 Cloud data isn't updating?
Extension: Go to Settings → Cloud Sync and click ⇄ Merge, or simply close and reopen the sidebar.
iPad / Mac: Switch to another app and switch back — sync runs automatically on foreground.
🔸 Accidentally deleted important markers?
Import your JSON backup if available. With Cloud Sync enabled, go to Cloud Snapshots → ⤓ Restore to recover a previous version.
🔸 How to sync between multiple computers?
Sign in with the same Supabase account on all devices. All profile snapshots are accessible everywhere, independent of Chrome Sync.