Examine source code of RSSHub Radar

{
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "i@diygod.me"
    }
  },
  "name": "RSSHub Radar",
  "description": "RSSHub Radar is a spin-off of RSSHub that helps you quickly discover and subscribe to RSS and RSSHub for your current site.",
  "version": "1.10.3",
  "homepage_url": "https://docs.rsshub.app",
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_icon": "rsshub.png",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://*/*",
        "http://*/*"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "background": {
    "page": "background.html",
    "persistent": true
  },
  "options_page": "options.html",
  "sandbox": {
    "pages": [
      "sandbox.html"
    ]
  },
  "permissions": [
    "tabs",
    "storage",
    "notifications",
    "alarms",
    "idle"
  ]
}