Examine source code of History ADV+

{
  "description": "Advanced browsing history logger",
  "manifest_version": 2,
  "name": "History ADV+",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "historyBackground.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "index.js"
      ]
    }
  ],
  "icons": {
    "32": "advancedhistory.svg"
  },
  "browser_action": {
    "browser_style": true,
    "default_title": "Advanced browsing history logger",
    "default_icon": {
      "32": "advancedhistory.svg"
    }
  },
  "version": "1.2"
}