Examine source code of Idlescape utilities

{
  "name": "Idlescape utilities",
  "version": "0.6.9",
  "manifest_version": 2,
  "description": "Quality of life improvements for Idlescape.",
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "default_locale": "en",
  "page_action": {
    "default_icon": "icons/icon19.png",
    "default_title": "Idlescape utilities",
    "default_popup": "src/popup/popup.html"
  },
  "permissions": [
    "https://idlescape.com/*",
    "https://www.idlescape.com/*",
    "https://dev.idlescape.com/*",
    "storage"
  ],
  "web_accessible_resources": [
    "icons/icon48.png",
    "src/popup/popup.html"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://idlescape.com/*",
        "https://www.idlescape.com/*",
        "https://dev.idlescape.com/*"
      ],
      "css": [
        "src/inject/inject.css"
      ]
    },
    {
      "matches": [
        "https://idlescape.com/*",
        "https://www.idlescape.com/*",
        "https://dev.idlescape.com/*"
      ],
      "js": [
        "src/inject/inject.js"
      ]
    }
  ]
}