Examine source code of Google Date Keeper

{
  "name": "Google Date Keeper",
  "version": "0.7.6resigned1",
  "author": "Little Spark",
  "description": "++ Date @ Google Search",
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "googledatekeeper@example.org"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "include_globs": [
        "*.google.*"
      ],
      "js": [
        "content_script.js"
      ],
      "run_at": "document_end"
    }
  ]
}