Examine source code of WWProxy

{
  "description": "WWProxy - https://www.facebook.com/wwproxy",
  "manifest_version": 3,
  "name": "WWProxy",
  "author": "WW",
  "version": "1.0",
  "homepage_url": "https://wwproxy.com/",
  "icons": {
    "48": "icons/icon.png",
    "96": "icons/icon96.png"
  },
  "action": {
    "default_icon": "icons/icon.png",
    "default_popup": "popup.html"
  },
  "host_permissions": [
    "https://wwproxy.com/*"
  ],
  "permissions": [
    "notifications",
    "storage",
    "proxy"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "daukhac@example.com",
      "strict_min_version": "91.1"
    }
  },
  "background": {
    "scripts": [
      "js/background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://*/*"
      ],
      "js": [
        "main.js"
      ]
    }
  ]
}