Examine source code of PDF tools

{
  "name": "PDF tools",
  "version": "1.1.0",
  "manifest_version": 2,
  "description": "Free PDF converter by fastdoc.online.",
  "icons": {
    "16": "icons/icon.png",
    "48": "icons/icon.png",
    "128": "icons/icon.png"
  },
  "default_locale": "en",
  "background": {
    "page": "background.html"
  },
  "homepage_url": "https://fastdoc.online/index.html",
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "PDF tools Extension",
    "default_popup": "popup.html"
  },
  "applications": {
    "gecko": {
      "id": "fastdoc@fastdoc.online"
    }
  }
}