Examine source code of Simple Podcast Player

{
  "manifest_version": 2,
  "name": "Simple Podcast Player",
  "version": "1.0",
  "description": "Listen to podcasts from RSS feeds or featured podcasts.",
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [
    "storage",
    "background",
    "<all_urls>"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a45b7f0b-dce7-4cc2-a927-da2060e3829d}"
    }
  }
}