Examine source code of Stop FITT

{
  "manifest_version": 2,
  "name": "Stop FITT",
  "description": "Bloque les sites Facebook, Instagram, Twitter et TikTok.",
  "author": "marsanaryas",
  "version": "1",
  "icons": {
    "192": "icon.png"
  },
  "browser_action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "app.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f6e882f1-af0b-4b5e-b3f1-ebc539ce76cc}"
    }
  }
}