Examine source code of Mactionary

{
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "mactionary@sechstein",
      "strict_min_version": "57.0"
    }
  },
  "version": "3.0.1resigned1",
  "author": "Sechstein",
  "name": "Mactionary",
  "description": "__MSG_Ext_Intro__",
  "default_locale": "en",
  "icons": {
    "16": "icon16.png",
    "32": "icon32.png",
    "300": "icon.png"
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "background": {
    "scripts": [
      "config.js",
      "lookup.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "js": [
        "config.js",
        "lookup.js",
        "content.js"
      ],
      "all_frames": true,
      "match_about_blank": true,
      "run_at": "document_start",
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "permissions": [
    "storage",
    "menus"
  ]
}