Examine source code of Burp Proxy Helper

{
  "manifest_version": 2,
  "name": "Burp Proxy Helper",
  "version": "1.0.0",
  "description": "Quickly toggle a PAC-based proxy to Burp Suite (default 127.0.0.1:8080) with a per-user bypass list. Read-only, no icons.",
  "permissions": [
    "proxy",
    "storage",
    "tabs",
    "contextMenus",
    "activeTab"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_title": "Burp Proxy Helper",
    "default_popup": "popup.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "burp-proxy-helper@example.com",
      "strict_min_version": "102.0"
    }
  }
}