Examine source code of Intool RSS Feeder

{
  "manifest_version": 3,
  "browser_specific_settings": {
    "gecko": {
      "id": "intool@intool.info"
    }
  },
  "name": "Intool RSS Feeder",
  "description": "Intool RSS Feed",
  "version": "0.1.4",
  "background": {
    "scripts": [
      "/background.js"
    ]
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "host_permissions": [
    "<all_urls>"
  ],
  "action": {
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "/content.js"
      ]
    }
  ],
  "options_page": "options.html",
  "devtools_page": "devtools.html",
  "icons": {
    "32": "icon_32.png",
    "64": "icon_64.png",
    "128": "icon_128.png"
  }
}