Examine source code of Duskmode for Reddit

{
  "manifest_version": 3,
  "name": "Duskmode for Reddit",
  "version": "1.1.7",
  "description": "An elegant, refined dark mode for old.reddit.com with OLED, Soft Dark, and Warm Dark themes. Auto-schedules based on sunset/sunrise.",
  "author": "David",
  "icons": {
    "16": "icons/icon-16.svg",
    "32": "icons/icon-32.svg",
    "48": "icons/icon-48.svg",
    "128": "icons/icon-128.svg"
  },
  "permissions": [
    "storage",
    "activeTab"
  ],
  "host_permissions": [
    "*://old.reddit.com/*",
    "*://www.reddit.com/*",
    "*://reddit.com/*",
    "*://nominatim.openstreetmap.org/*",
    "*://api.sunrisesunset.io/*",
    "*://ipapi.co/*",
    "*://ipwho.is/*"
  ],
  "action": {
    "default_icon": {
      "16": "icons/icon-16.svg",
      "32": "icons/icon-32.svg",
      "48": "icons/icon-48.svg"
    },
    "default_title": "Reddit Night Mode",
    "default_popup": "popup/popup.html"
  },
  "background": {
    "scripts": [
      "background/background.js"
    ],
    "type": "module"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "duskmode@reddit-night-mode.com",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  },
  "content_scripts": [
    {
      "matches": [
        "*://old.reddit.com/*",
        "*://www.reddit.com/*",
        "*://reddit.com/*"
      ],
      "js": [
        "content/content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "css/*.css"
      ],
      "matches": [
        "*://old.reddit.com/*",
        "*://www.reddit.com/*",
        "*://reddit.com/*"
      ]
    }
  ]
}