Hangouts with Tab Key

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "manifest_version": 2,
  "name": "Hangouts with Tab Key",
  "description": "This extension lets you use the tab key to cycle through your Google Hangout windows",
  "version": "1.0",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "icon16.png",
    "48": "icon48.png",
    "128": "icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://mail.google.com/*",
        "https://inbox.google.com/*"
      ],
      "js": [
        "host-site.js"
      ]
    },
    {
      "matches": [
        "https://talkgadget.google.com/*"
      ],
      "all_frames": true,
      "js": [
        "hangout-window.js"
      ],
      "run_at": "document_end"
    }
  ]
}