Examine source code of Tracup

{
  "description": "Tracup －可以让你在测试的时候方便的在网站的任何位置进行截图，标记，并且直接上传截图到 Tracup。这是 Tracup www.tracup.com）提供的插件。",
  "manifest_version": 2,
  "name": "Tracup",
  "version": "0.1.9resigned1",
  "homepage_url": "https://www.tracup.com/",
  "icons": {
    "48": "res/images/icon48.png"
  },
  "applications": {
    "gecko": {
      "id": "bugcloudextension@pgyer.com",
      "strict_min_version": "45.0"
    }
  },
  "background": {
    "scripts": [
      "res/scripts/app.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "19": "res/images/icon19.png",
      "36": "res/images/icon36.png"
    },
    "default_title": "Tracup"
  },
  "content_scripts": [
    {
      "js": [
        "res/scripts/content.js"
      ],
      "matches": [
        "https://www.tracup.com/*",
        "https://bug.pgyer.com/*",
        "http://*.pgyer.yunhuiju.com/*"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "storage",
    "tabs",
    "<all_urls>",
    "activeTab",
    "cookies",
    "http://*.yunhuiju.com/",
    "https://bug.pgyer.com/",
    "https://www.tracup.com/"
  ]
}