Examine source code of Sussify

{
  "manifest_version": 2,
  "name": "Amogus",
  "version": "1.1",
  "description": "Sussify web pages with this amazing extension!",
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/sus-32.png",
    "default_title": "Amogus",
    "default_popup": "popup/popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b9956e0f-fe9c-4834-8c69-1147b48b13b3}",
      "strict_min_version": "42.0"
    }
  },
  "icons": {
    "16": "icons/sus-16.png",
    "32": "icons/sus-32.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "script.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "images/*"
  ]
}