Examine source code of Yugipedia Redirect

{
  "name": "Yugipedia Redirect",
  "description": "Redirect from Yu-Gi-OH! Wikia to Yugipedia.",
  "version": "1.2.1resigned1",
  "manifest_version": 2,
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "./assets/16x16.png",
      "48": "./assets/48x48.png",
      "128": "./assets/128x128.png"
    }
  },
  "icons": {
    "16": "./assets/16x16.png",
    "48": "./assets/48x48.png",
    "128": "./assets/128x128.png"
  },
  "permissions": [
    "<all_urls>",
    "webRequest",
    "webRequestBlocking",
    "storage"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{2366a5e6-5d4b-4d24-b88a-8cd3b6b6c4d8}"
    }
  }
}