Examine source code of Retro Revive

{
  "manifest_version": 2,
  "name": "Retro Revive",
  "version": "1.1.0",
  "description": "New tab addon that takes you on a journey back in time.",
  "browser_specific_settings": {
    "gecko": {
      "id": "product@togonetworksltd.com",
      "strict_min_version": "58.0"
    }
  },
  "icons": {
    "16": "assets/icons/16px.png",
    "96": "assets/icons/96px.png",
    "128": "assets/icons/128px.png"
  },
  "browser_action": {
    "default_icon": {
      "16": "assets/icons/16px.png"
    },
    "default_title": "Retro Revive"
  },
  "author": "Togo Networks Ltd",
  "homepage_url": "https://www.retronewtab.com/",
  "permissions": [
    "cookies",
    "storage",
    "*://*.retronewtab.com/*"
  ],
  "chrome_url_overrides": {
    "newtab": "new-tab.html"
  },
  "web_accessible_resources": [
    "assets/icons/*.png"
  ],
  "background": {
    "page": "main.html",
    "persistent": false
  }
}