Examine source code of 3G Proxy

{
  "version": "1.9.2",
  "manifest_version": 2,
  "description": "3G Proxy Firefox extension",
  "name": "3G Proxy",
  "icons": {
    "16": "./resources/build/icon-16x16.png",
    "48": "./resources/build/icon-48x48.png",
    "128": "./resources/build/icon-128x128.png"
  },
  "applications": {
    "gecko": {
      "id": "developers@3gproxy.com",
      "strict_min_version": "57.0"
    }
  },
  "permissions": [
    "notifications",
    "http://*/*",
    "proxy",
    "tabs",
    "unlimitedStorage",
    "storage",
    "<all_urls>",
    "webRequest",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": [
      "./code/libs/jquery-3.3.1.min.js",
      "./code/base.background.js",
      "./firefox.background.js"
    ]
  },
  "commands": {
    "open-option": {
      "suggested_key": {
        "default": "Alt+O"
      },
      "description": "Open option page"
    }
  },
  "browser_action": {
    "default_icon": "./resources/images/3g_flags/1.logo_off.png",
    "default_title": "3g proxy",
    "default_popup": "./views/index.html"
  },
  "content_security_policy": "script-src 'self' 'unsafe-eval'; object-src 'self'"
}