Examine source code of Stranger Things Banner

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Stranger Things Banner",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center center"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(125, 6, 15, 0.3)",
      "toolbar_text": "rgb(249, 246, 247)",
      "frame": "rgb(142, 179, 201)",
      "tab_background_text": "rgb(233, 211, 218)",
      "toolbar_field": "rgba(248, 222, 243, 0.7)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgb(248, 112, 140)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(98, 102, 183)",
      "tab_loading": "rgb(248, 112, 140)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{e0607440-0773-43d1-bb1c-ad7178c29210}"
    }
  }
}