Examine source code of Enviro-Shade

{
  "manifest_version": 3,
  "name": "Enviro-Shade",
  "version": "1.4.7",
  "description": "Adds a customizable color banner and watermark to websites to clearly identify your environment (e.g., PROD, QA, LOCAL).",
  "author": "Nico Koeppe",
  "homepage_url": "https://github.com/nkoeppe/Enviro-Shade",
  "permissions": [
    "tabs",
    "storage",
    "webNavigation"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "service_worker": "background.js",
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_start",
      "all_frames": false
    }
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true
  },
  "action": {
    "default_title": "Enviro-Shade"
  },
  "icons": {
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png",
    "128": "icons/icon-128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "env-color-banner@fancyguysdev.de",
      "strict_min_version": "109.0"
    }
  }
}