Examine source code of Multicolor Windows

{
  "manifest_version": 2,
  "name": "Multicolor Windows",
  "version": "1.1",
  "description": "Assign unique colors to each Firefox window with light/dark theme support",
  "homepage_url": "https://github.com/nirine/firefox-multicolor-window-theme",
  "background": {
    "scripts": [
      "js/main.js"
    ],
    "persistent": true
  },
  "permissions": [
    "tabs",
    "theme",
    "storage",
    "activeTab",
    "<all_urls>"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{959172e0-c3e9-4ef0-acf8-e6f429d58179}"
    }
  }
}