Examine source code of Cache Companion

{
  "manifest_version": 3,
  "name": "Cache Companion",
  "version": "2.1.0",
  "description": "Track geocaching challenge progress — Jasmer, Fizzy, and more.",
  "icons": {
    "16": "icon.svg",
    "32": "icon.svg",
    "48": "icon.svg",
    "128": "icon.svg"
  },
  "permissions": [
    "storage",
    "tabs"
  ],
  "host_permissions": [
    "https://www.geocaching.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://www.geocaching.com/geocache/GC*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "https://www.geocaching.com/play/map*"
      ],
      "js": [
        "map.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "action": {
    "default_title": "Cache Companion",
    "default_icon": {
      "16": "icon.svg",
      "32": "icon.svg",
      "48": "icon.svg",
      "128": "icon.svg"
    },
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "cache-companion@extension",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}