Examine source code of Chrometa Time Tracker

{
  "manifest_version": 2,
  "name": "Chrometa Time Tracker",
  "version": "1.0",
  "description": "Tracks time spent on websites and applications automatically, similar to Chrometa’s desktop tools",
  "icons": {
    "48": "icons/Chrometa_logo-48x48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "chrometa.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{935b132f-5f59-452a-b5e6-02765999a4d8}"
    }
  }
}