Examine source code of wxIF

{
  "manifest_version": 2,
  "name": "wxIF",
  "version": "0.3resigned1",
  "default_locale": "en",
  "description": "__MSG_extensionDescription__",
  "homepage_url": "https://github.com/gcp/wxif",
  "icons": {
    "32": "icons/fxif.png"
  },
  "permissions": [
    "<all_urls>",
    "contextMenus",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "backgroundscript.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8b3ee44a-0805-4c2c-acef-15aab34fbd20}"
    }
  }
}