Examine source code of Sneetches for GitHub

{
  "name": "Sneetches for GitHub",
  "short_name": "Sneetches",
  "version": "1.4.2",
  "author": "Kevin Esensoy",
  "description": "Adds stars next to GitHub repo links",
  "homepage_url": "https://github.com/kesensoy/sneetches",
  "manifest_version": 3,
  "browser_specific_settings": {
    "gecko": {
      "id": "sneetches@kesensoy.github.io",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "host_permissions": [
    "https://api.github.com/*"
  ],
  "optional_host_permissions": [
    "*://*/*"
  ],
  "permissions": [
    "storage"
  ],
  "icons": {
    "48": "images/icon128.png",
    "128": "images/icon128.png"
  },
  "background": {
    "service_worker": "service-worker.js",
    "type": "module",
    "scripts": [
      "service-worker.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://*/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "style.css"
      ],
      "run_at": "document_start"
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "action": {
    "default_icon": {
      "32": "images/icon32.png",
      "48": "images/icon128.png"
    },
    "default_popup": "options.html"
  }
}