Examine source code of Website Scrub

{
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "description": "Allows the user to delete history of a particular website.",
  "homepage_url": "https://github.com/nabendu82/Addons",
  "page_action": {
    "default_title": "Website History delete",
    "default_popup": "history.html",
    "default_icon": "icons/logo_64.png"
  },
  "icons": {
    "32": "icons/logo_32.png",
    "64": "icons/logo_64.png",
    "128": "icons/logo_128.png"
  },
  "permissions": [
    "activeTab",
    "history",
    "tabs"
  ],
  "manifest_version": 2,
  "name": "Website History Delete",
  "version": "1.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "{37925b9f-d875-49e9-96dc-a86a538f000b}"
    }
  }
}