Webview Box Reflection Bug

manifest.json

{
  "update_url": "https://clients2.google.com/service/update2/crx",
  "name": "Webview Box Reflection Bug",
  "description": "Demonstration of a rendering bug",
  "version": "1.1",
  "manifest_version": 2,
  "app": {
    "background": {
      "scripts": [
        "background.js"
      ]
    }
  },
  "icons": {
    "256": "256.png"
  },
  "webview": {
    "partitions": [
      {
        "name": "trusted",
        "accessible_resources": [
          "*.html",
          "*.png",
          "*.js"
        ]
      }
    ]
  },
  "permissions": [
    "webview",
    "https://*/",
    "http://*/"
  ]
}