TabVCR Docs

Setup

TabVCR needs Chrome 126 or newer. After installing:

1. Open TabVCR's Extension options.
2. Choose your output folder and grant access. Recordings are written directly into this folder as they record. Chrome may ask you to reconnect the folder after a restart — TabVCR checks this before each recording and will prompt you if needed.
3. Pick your preferences: output format, resolution, window sizing, popup start delay, audio monitoring, and notifications (all explained below).
4. Check the Keyboard shortcut section. It shows the shortcut actually assigned in your Chrome profile — the suggested default is Cmd+Shift+7 (Mac) or Ctrl+Shift+7 (Windows/Linux). If it says Not assigned, use the button to open Chrome's shortcut settings and assign one.

Recording a tab

1. Cue it up. Load the video and pause it where the recording should begin. The Chrome window can be normal or maximized, but not in operating-system fullscreen.
2. Start. Two ways:
   • Keyboard shortcut — starts immediately with an automatic filename.
   • Click TabVCR — review or edit the filename (prefilled from the tab title), then hit Start recording. Popup starts wait through your chosen 2–3 second delay (default 3) so you can move the pointer out of frame; the badge counts down.
3. It takes over. For a standard HTML5 video, TabVCR sizes the window per your preference, moves the video into a black tab-filling layer, waits for the badge to read REC, and starts playback.
4. Walk away. Chrome records the tab, not your screen — cover the window with other apps or send it to the background. Just don't close, navigate, or move the recording tab to another window.
5. It stops itself when the video ends. To stop early, return to that tab and press the shortcut (or open TabVCR and choose Stop recording) — everything captured so far is finalized and kept.

Afterward, TabVCR restores the video to its original place on the page and returns the window to its original size and state. If you moved or resized the window yourself mid-recording, TabVCR treats that as your call and leaves it alone.

Badge meanings

Don't close Chrome until the badge changes from REC to OK.

Output

Why WebM by default? It produced better A/V synchronization in deterministic Chrome-for-Testing trials. Native MP4 works on tested builds but showed roughly 0.16–0.17 s of median audio lag in the timing fixture. TabVCR checks format support before creating a file, never disguises one format as another, and never re-transcodes your recording.

Filenames are scrubbed of characters that are invalid on common filesystems, and collisions get (2), (3), and so on.

Preferences

• Output format — WebM (recommended) or experimental native MP4.
• Resolution — 720p or 1080p.
• Window sizing — largest fitting 16:9 area, match the output size when it fits, or don't resize at all.
• Popup start delay — off, 2 s, or 3 s (default). Gives you time to move the pointer after clicking Start. Shortcut starts are always immediate.
• Mute the recorded tab — keeps tab audio in the file while silencing your speakers.
• Completion notification — optional, privacy-safe: a generic saved/partial/failed notice with no page title, filename, or website in it. Badges remain the fallback.

Multiple simultaneous recordings

Every tab is its own VCR. The popup and the keyboard shortcut always control the current tab; other tabs keep recording independently, each with its own countdown, badge, and stop control. To record two things at once, just switch to the second tab and start TabVCR there too.

Capacity is hardware-dependent. In our isolated release lab, an Apple M4 MacBook Air with 24 GB of memory sustained four simultaneous 720p WebM recordings in separate windows with complete frame sequences, and two tabs sharing one window also passed. Heavier loads — six-plus sessions, or two simultaneous 1080p recordings — failed our strict quality gates on that machine. Those are measured results, not promises: your ceiling depends on your computer, Chrome version, formats, source complexity, and disk speed. If quality suffers, reduce concurrency or resolution.

Honest limits

• TabVCR does not bypass content protection.
• No OS fullscreen. TabVCR uses a tab-sized layer, not the Fullscreen API. It also refuses to resize a window that's minimized or in OS fullscreen — restore it to a normal window first, or choose Do not resize.
• Pages with multiple videos: TabVCR rescans each time and picks the largest visible accessible video — put the one you want in the page's main player before starting.
• Keep the tab where it is. Closing, navigating, or moving a recording tab to a different window ends that recording (safely — the captured portion is kept).
• Looping videos never fire an end event — stop those manually.
• Format availability varies by machine. If MP4 isn't available on your Chrome under load, TabVCR tells you before creating the file. Prefer WebM when sync matters most.
• 1080p can't add detail that the source video or rendered tab never had.
• Browser-internal pages (like chrome://) can't be recorded.
• A site that removes or replaces its video element mid-recording may require a manual stop and a page reload afterward.

Permissions

There is no tabs, downloads, debugger, microphone, webcam, <all_urls>, or network host permission. See the privacy policy for the full data-handling story.