Examine source code of Phi-Web Filter

{
  "manifest_version": 3,
  "name": "Phi-Web Filter",
  "version": "0.3.0",
  "description": "Wandelt jede Webseite in ein ruhiges Monochrom um. Anthrazit und Gebrochenweiß — kein Tracking, keine Datenerhebung.",
  "icons": {
    "16": "icons/phi-16.png",
    "32": "icons/phi-32.png",
    "48": "icons/phi-48.png",
    "96": "icons/phi-96.png"
  },
  "permissions": [
    "storage",
    "activeTab"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_title": "Phi-Web Filter",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "css": [
        "content.css"
      ],
      "js": [
        "content.js"
      ],
      "all_frames": true,
      "match_about_blank": true,
      "match_origin_as_fallback": true,
      "run_at": "document_start"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "phi@levian.dev",
      "data_collection_permissions": {
        "required": [
          "none"
        ],
        "optional": []
      }
    }
  }
}