Examine source code of downloadResources

{
  "manifest_version": 2,
  "name": "downloadResources",
  "author": "baizp",
  "version": "1.1",
  "description": "下载资源",
  "browser_action": {
    "default_icon": {
      "16": "icon.png",
      "32": "icon.png"
    },
    "default_title": "下载",
    "default_popup": "popup/popup.html"
  },
  "permissions": [
    "downloads",
    "downloads.open",
    "devtools",
    "webRequest",
    "<all_urls>",
    "storage",
    "webRequestBlocking",
    "tabs",
    "menus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{6a8e483d-d877-42de-8e3b-2d11169b7e6a}"
    }
  }
}