Examine source code of warning update your fox

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "warning ",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg",
        "images/1.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "left bottom",
        "right center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat",
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(18, 145, 225, 0)",
      "toolbar_text": "rgb(60, 198, 226)",
      "frame": "rgb(24, 23, 19)",
      "tab_background_text": "rgb(236, 14, 11)",
      "toolbar_field": "rgba(5, 4, 4, 0.2)",
      "toolbar_field_text": "rgb(251, 52, 10)",
      "tab_line": "rgb(251, 20, 10)",
      "popup": "rgb(12, 13, 12)",
      "popup_text": "rgb(222, 57, 22)",
      "tab_loading": "rgb(251, 20, 10)"
    }
  }
}