Browser Sync - 浏览器数据迁移助手

A browser extension (Manifest V3) that migrates bookmarks, cookies (login state), pinned tabs, and browsing history between Chromium-based browsers. The extension uses Chrome APIs (chrome.bookmarks, chrome.cookies, chrome.tabs, chrome.history) to read/write data natively, bypassing DPAPI encryption issues entirely.

Extension Source Location

The complete extension source is bundled with this skill at: extension/

Key files:

• manifest.json - Extension config (Manifest V3)
• core.js - SyncEngine object with all export/import logic
• popup.html + popup.css + popup.js - UI layer
• background.js - Service worker (minimal)
• icons/ - Extension icons (16/48/128px)

Supported Browsers

All Chromium-based: 360安全浏览器, 360极速浏览器, Chrome, Edge, 夸克, 豆包, Brave, Opera, Vivaldi, etc.

What Can Be Migrated

Cannot migrate via extension: Saved passwords (security restriction — must be exported manually from browser settings), autofill data, extension data.

Workflow 1: Deploy the Extension

Guide the user through these steps:

1. Copy extension folder to a convenient location (e.g., user's desktop or selected working folder):
• Copy the entire extension/ directory from this skill's location

1. Load in browser (developer mode):
• 360安全浏览器: navigate to se://extensions/
• 360极速浏览器: navigate to chrome://extensions/
• Chrome: navigate to chrome://extensions/
• Edge: navigate to edge://extensions/
• Others: similar ://extensions/ URL

1. Enable developer mode (toggle in top-right corner)

1. Click "Load unpacked" → select the extension/ folder

1. Verify the icon appears in the browser toolbar

Workflow 2: Export Data (Source Computer)

1. Click extension icon → click "导出" (Export)
2. Select data types (all checked by default)
3. Click "开始导出" → save the .json file
4. Transfer file to target computer (USB, cloud, chat, etc.)

The export file format:

{
  "_meta": {
    "version": "1.0",
    "source_browser": "360 浏览器",
    "exported_at": "2026-06-10T...",
    "data_types": ["bookmarks", "cookies", "tabs", "history"]
  },
  "bookmarks": [{ "title": "...", "type": "folder", "children": [...] }],
  "cookies": [{ "url": "...", "name": "...", "value": "...", "domain": "..." }],
  "tabs": { "pinned": [{ "url": "...", "title": "..." }], "regular": [...] },
  "history": [{ "url": "...", "title": "...", "visitCount": 5 }]
}

Workflow 3: Import Data (Target Computer)

1. Install the extension on target browser (same steps as Workflow 1)
2. Click extension icon → click "导入" (Import)
3. Select the .json migration file
4. Review detected data types and counts
5. Choose bookmark mode: "合并" (merge, default) or "替换" (replace)
6. Click "开始导入"

Workflow 4: Customize the Extension

When the user requests modifications, edit the files in the extension/ directory. Common customization scenarios:

Add new data type support

1. Add export method to SyncEngine in core.js:

async exportNewType() {
  // Use appropriate chrome.* API
  return new Promise((resolve, reject) => { ... });
}

1. Add it to buildExportFile() with a new conditional block
2. Add corresponding import method
3. Add UI checkbox in popup.html and handle in popup.js
4. Add permission in manifest.json if needed

Modify UI

• popup.html - Structure and layout
• popup.css - Styling (gradient header, card-based design)
• popup.js - Interaction logic and view switching

Adjust export behavior

• Change history days limit: modify exportHistory(90) parameter
• Change max history results: modify maxResults: 50000
• Change cookie expiration handling: modify the importCookies expiry check
• Add domain filtering: add filter logic in exportCookies or importCookies

Add encryption to export file

Currently cookies are stored in plaintext in the JSON file. To encrypt:

• Use crypto.subtle API in the service worker
• Encrypt sensitive fields (cookie values) before writing to export file
• Prompt for password on import and decrypt before writing cookies

Workflow 5: Password Migration Guidance

Passwords cannot be migrated via extension. Guide the user:

1. Source browser: Settings → search "密码" → Password Manager → Export passwords → save CSV
2. Transfer CSV to target computer
3. Target browser: Password Manager → Import passwords → select CSV

The extension UI includes a built-in help modal for this — direct users to click "查看操作方法" on the main screen.

Troubleshooting

Technical Notes

• The extension uses Manifest V3 (required for modern Chromium browsers)
• The permission is needed for chrome.cookies API to access cookies from all domains
• Cookie values are stored in plaintext in the export JSON — remind users to keep the file secure and delete after use
• The chrome.cookies.set() API handles re-encryption automatically on the target browser
• Bookmark IDs are not preserved during migration (new IDs are assigned by the target browser)
• For detailed API reference and architecture, see reference.md