Examine source code of QR Code for Firefox

{
  "manifest_version": 3,
  "name": "QR Code for Firefox",
  "version": "1.1.2.1",
  "description": "QR Code for Firefox generates QR codes independently, simple and fast, and can be generated immediately for 256 colors of any size（below 320px by 320px）。",
  "icons": {
    "48": "icons/Super_QR-48.png"
  },
  "permissions": [
    "tabs"
  ],
  "host_permissions": [
    "*://*/*"
  ],
  "action": {
    "default_icon": {
      "32": "icons/Super_QR-32.png"
    },
    "default_title": "QR Code for Firefox",
    "default_popup": "popup/SuperQR.html"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "js": [
        "scripts/content.js"
      ],
      "matches": [
        "<all_urls>"
      ]
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "*"
      ],
      "matches": []
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "netshow-vip@sohu.com"
    }
  }
}