Examine source code of PhotoSync

{
  "manifest_version": 2,
  "name": "PhotoSync",
  "description": "Syncs photo and comment data on your Facebook photos",
  "author": "Runaway Bytes",
  "version": "1.1resigned1",
  "icons": {
    "48": "icon-48.png",
    "128": "icon-128.png",
    "256": "icon-256.png"
  },
  "options_ui": {
    "page": "options.html"
  },
  "content_scripts": [
    {
      "run_at": "document_end",
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "version.js"
      ]
    },
    {
      "run_at": "document_end",
      "matches": [
        "https://www.facebook.com/*"
      ],
      "js": [
        "link.js"
      ]
    },
    {
      "run_at": "document_start",
      "matches": [
        "https://www.facebook.com/*"
      ],
      "js": [
        "content-mask.js"
      ]
    }
  ],
  "permissions": [
    "*://*/*",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{68ac4f78-075d-45cf-84ae-61879910219d}"
    }
  }
}