Examine source code of PerfectPost

{
  "name": "__MSG_extensionName__",
  "description": "__MSG_extensionDescription__",
  "version": "26.5.26",
  "short_name": "PerfectPost",
  "homepage_url": "https://perfectpost.social",
  "manifest_version": 3,
  "default_locale": "en",
  "icons": {
    "16": "images/pp_icon16.png",
    "32": "images/pp_icon32.png",
    "48": "images/pp_icon48.png",
    "128": "images/pp_icon128.png",
    "256": "images/pp_icon256.png",
    "512": "images/pp_icon512.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "perfect-post@prototyper.fr",
      "strict_min_version": "67.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.linkedin.com/*"
      ],
      "js": [
        "firefox-fix.js",
        "linkedin.js"
      ],
      "css": [
        "linkedin.css"
      ]
    },
    {
      "matches": [
        "*://*.perfectpost.fr/*"
      ],
      "run_at": "document_start",
      "js": [
        "perfectpost.js"
      ]
    }
  ],
  "permissions": [
    "alarms",
    "storage",
    "tabs",
    "webRequest"
  ],
  "optional_permissions": [
    "notifications"
  ],
  "host_permissions": [
    "*://*.linkedin.com/*"
  ],
  "action": {
    "default_popup": "popup.html",
    "default_title": "PerfectPost"
  },
  "web_accessible_resources": [
    {
      "resources": [
        "chat.html",
        "chat-proxy.js"
      ],
      "matches": [
        "*://*.linkedin.com/*"
      ]
    }
  ]
}