Examine source code of FileFast: File Transfer & Gmail

{
  "manifest_version": 3,
  "name": "FileFast: File Transfer & Gmail",
  "description": "Create one secure FileFast transfer from files or a folder and insert its link into Gmail.",
  "version": "0.1.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "firefox@file.fast",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo",
          "personalCommunications",
          "personallyIdentifyingInfo"
        ]
      }
    }
  },
  "action": {
    "default_title": "Open FileFast"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "sidebar_action": {
    "default_title": "FileFast",
    "default_panel": "sidepanel.html",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png"
    },
    "open_at_install": false
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://file.fast/*",
    "https://mail.google.com/*",
    "https://storage01.file.fast/*",
    "https://*.r2.cloudflarestorage.com/*"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://mail.google.com/*"
      ],
      "js": [
        "gmail-content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "content_security_policy": {
    "extension_pages": "script-src 'self'; object-src 'none'"
  }
}