Examine source code of Sync Bookmarks

{
  "manifest_version": 2,
  "version": "1.7resigned1",
  "name": "Sync Bookmarks",
  "icons": {
    "48": "icons/icon.png",
    "96": "icons/icon.png"
  },
  "description": "Synchronise bookmarks",
  "browser_action": {
    "browser_style": true,
    "default_icon": "icons/icon.png",
    "default_title": "Sync Bookmarks",
    "default_popup": "popup.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "activeTab",
    "storage",
    "identity",
    "*://www.googleapis.com/*",
    "*://accounts.google.com/*",
    "*://apis.google.com/*"
  ],
  "applications": {
    "gecko": {
      "id": "sync-bookmarks@ricwtk",
      "strict_min_version": "42.0"
    }
  }
}