Examine source code of Fast Image Download

{
  "manifest_version": 2,
  "name": "Fast Image Download",
  "version": "1.0",
  "description": "Downloads images fast",
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "fast.js"
      ],
      "run_at": "document_start"
    }
  ]
}