Examine source code of To Top Android

{
  "name": "To Top Android",
  "version": "1.1.2resigned1",
  "description": "Menu item which scrolls page to top",
  "manifest_version": 2,
  "applications": {
    "gecko": {
      "id": "to-top@mortalis.org"
    }
  },
  "background": {
    "scripts": [
      "main-to-top.js"
    ]
  },
  "browser_action": {
    "default_title": "To Top"
  },
  "permissions": [
    "tabs",
    "<all_urls>"
  ]
}