Examine source code of Save to Bookmark OS

{
  "applications": {
    "gecko": {
      "id": "dave@bookmarkos.com"
    }
  },
  "manifest_version": 2,
  "name": "Save to Bookmark OS",
  "description": "Save bookmarks easily to Bookmark OS",
  "version": "2.0.1",
  "icons": {
    "16": "img/icon16.png",
    "48": "img/icon48.png",
    "128": "img/icon128.png"
  },
  "permissions": [
    "tabs",
    "<all_urls>"
  ],
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "js/meta_data.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_action": {
    "default_icon": {
      "19": "img/icon19.png",
      "38": "img/icon38.png"
    },
    "default_popup": "popup.html"
  }
}