Chrome Extension Sample

manifest.json

{
  "manifest_version": 2,
  "name": "My 4th extension",
  "version": "0.1",

  "description": "testing purpose",

  "permissions": [
    "activeTab"
  ],

  "content_scripts": [
    {
      "matches": ["http://dotinstall.com/*"],
      "js": ["myscript.js"]
    }
  ]
}

myscript.js

alert("dotinstall!");