Amanda Hangouts!

inject.js

alert('Hello!');

manifest.json

{
  "name": "Amanda for Google Plus",
  "version": "0.0.1",
  "description": "Amanda in Google Plus",
  "content_scripts": [{
    "matches": ["https://plus.google.com/107982618909749811163/*"],
    "js": ["inject.js"],
    "run_at": "document_end",
    "all_frames": true
  }]
}