Examine source code of Anime Wallpapers

{
  "manifest_version": 2,
  "name": "Anime Wallpapers",
  "version": "4.3",
  "description": "Displays a anime background image (random) every time you open a new tab.",
  "applications": {
    "gecko": {
      "id": "{852f90fd-f477-48ca-9025-a0b417d8d863}"
    }
  },
  "content_security_policy": "script-src 'self'; object-src 'self' ",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "browser_action": {
    "default_title": "Anime"
  },
  "chrome_settings_overrides": {
    "homepage": "index.html"
  },
  "permissions": [
    "storage"
  ]
}