Examine source code of Modus

{
  "applications": {
    "gecko": {
      "id": "modus@kan.onl"
    }
  },
  "author": "Kanon Lo",
  "content_scripts": [
    {
      "matches": [
        "https://*/*",
        "http://*/*"
      ],
      "js": [
        "assets/js/content_scripts.js"
      ]
    }
  ],
  "description": "Inject user-generated CSS and JavaScript into all webpages.",
  "icons": {
    "16": "assets/images/modus-96.png",
    "32": "assets/images/modus-96.png",
    "48": "assets/images/modus-96.png",
    "96": "assets/images/modus-96.png",
    "128": "assets/images/modus-128.png"
  },
  "manifest_version": 2,
  "name": "Modus",
  "options_ui": {
    "page": "assets/views/options.html"
  },
  "permissions": [
    "storage"
  ],
  "version": "0.0.101"
}