Examine source code of FontTrail

{
  "manifest_version": 3,
  "name": "FontTrail",
  "version": "1.0.0",
  "description": "Analyze real font-family usage density and fallback patterns across visible page text.",
  "icons": {
    "48": "marks/icon-48.png",
    "96": "marks/icon-96.png",
    "128": "marks/icon-128.png"
  },
  "action": {
    "default_title": "FontTrail",
    "default_popup": "studio/panel.html",
    "default_icon": {
      "48": "marks/icon-48.png"
    }
  },
  "options_ui": {
    "page": "prefs/options.html",
    "open_in_tab": true
  },
  "permissions": [
    "activeTab",
    "scripting",
    "storage",
    "tabs",
    "clipboardWrite"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{0ca80d25-56e0-4a1e-8952-7017b420cad3}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}