Google Play Music Tab Close Alarm

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Google Play Music Tab Close Alarm",
  "version": "2015.13.5",
  "icons": {
    "16": "/img/icons/icon_16.png",
    "48": "/img/icons/icon_48.png",
    "128": "/img/icons/icon_128.png"
  },
  "description": "When listening to music, you'll get a warning before you close the Play Music Tab. Never accidentally close it again.",
  "content_scripts": [
    {
      "matches": [
        "https://play.google.com/music/listen*"
      ],
      "js": [
        "/js/content_script.js"
      ]
    }
  ],
  "content_security_policy": "script-src 'self' https://www.google-analytics.com; object-src 'self'",
  "background": {
    "page": "background.html"
  },
  "manifest_version": 2
}