Scroll Screenshot

A modern, high-precision Chrome Extension (Manifest V3) that automatically captures consecutive visible viewports, scrolls down the page, and saves all captured screenshots directly to your ~/Downloads/ directory in one batch.

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✨ Features

• Automated Scrolling Loop: Captures visible screen area $\to$ buffers in memory $\to$ scrolls down $\to$ repeats until the bottom of the page is reached.
• Smart Container & Layer Detection:
  • Automatically identifies whether scrolling belongs to the window or a nested scrollable container (e.g., side drawers, comment panels, or modal dialogs).
  • Designed to intelligently target complex layouts (such as Douyin/TikTok comment panels) rather than triggering background video switches.
• Batch Export (No Spam Dialogs):
  • Screenshots are buffered in memory during the capture process without triggering repeated download popups.
  • Generates a single .zip file archive (or batch image sequence) on completion.
• Clean Native Rendering: Does not attach invasive debuggers or trigger viewport resize banners. 100% preserves original layout and pixel ratio.
• Zero External Dependencies: Pure JavaScript, lightweight, privacy-focused (all operations happen locally on your machine).
• Internationalization (i18n):
  • Default: English
  • Fallback: Chinese (zh_CN) when system language is Chinese.

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🚀 Installation

1. Clone or download this repository:

   git clone https://github.com/your-username/scroll-screenshot.git

2. Open Google Chrome and navigate to:

   chrome://extensions
   

3. Enable Developer mode in the top-right corner.
4. Click Load unpacked and select the extension folder (chrome_extension).

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📖 How to Use

1. Navigate to the webpage you want to capture.
2. Click the Scroll Screenshot extension icon in your toolbar (or press Alt + Shift + S).
3. (Optional) Adjust your settings in the popup:
   • Delay after scroll: Delay in milliseconds to wait for lazy-loaded images or DOM rendering (default: 1000ms).
   • Max shots: Maximum number of viewports to capture (0 = unlimited until the page bottom).
   • Overlap: Pixel overlap between adjacent screenshots to prevent missing split text lines.
   • Format: PNG or JPEG.
   • Save Method: Pack into a single ZIP file (default) or Save as individual images.
   • Subfolder: Optional subfolder under your ~/Downloads/ directory.
   • Scroll to top before starting: Start capturing from the beginning of the page.
4. Click Start Capture (or press Alt + Shift + S).
5. The extension will automatically scroll and capture. Click Stop & Save at any time to finish early and save whatever has been captured so far.

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⚙️ Chrome Download Settings Tip

If you choose to export individual images and Chrome keeps prompting you with a "Save As" file dialog for each screenshot:

1. Go to chrome://settings/downloads.
2. Disable "Ask where to save each file before downloading".

(When exporting as a ZIP file, only a single prompt will appear at most).

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📁 Project Structure

├── manifest.json         # Manifest V3 configuration & permissions
├── background.js        # Background service worker (capture & scroll logic)
├── popup.html           # Popup settings interface
├── popup.js             # Popup controls & options persistence
├── popup.css            # Clean modern styling
├── offscreen.html       # Offscreen document host
├── offscreen.js         # Zero-dependency in-memory ZIP packager & Blob builder
└── _locales/
    ├── en/messages.json # English translations (default)
    ├── zh/messages.json # Chinese translations
    └── zh_CN/messages.json

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🔒 Privacy & Permissions

• scripting & host_permissions (<all_urls>): Required to scroll the target page and determine content boundaries.
• downloads: Required to save screenshots to your Downloads folder.
• storage: Preserves user preferences across sessions.
• tabs: Queries the active tab and captures visible viewports.
• offscreen: Converts screenshots into an in-memory zip archive without blocking extension service workers.

No tracking. No analytics. No external network requests.

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📄 License

MIT License