Examine source code of Rain World

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "rain world",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right center"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(0, 0, 0, 0)",
      "toolbar_text": "rgb(248, 112, 140)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(90, 224, 199)",
      "toolbar_field": "rgba(9, 9, 9, 0.83)",
      "toolbar_field_text": "rgb(90, 224, 199)",
      "tab_line": "rgb(248, 112, 140)",
      "popup": "rgb(0, 0, 0)",
      "popup_text": "rgb(90, 224, 199)",
      "icons": "rgb(255, 167, 190)",
      "ntp_background": "rgb(0, 0, 0)",
      "ntp_text": "rgb(90, 224, 199)",
      "popup_highlight_text": "rgb(255, 255, 255)",
      "popup_highlight": "rgba(90, 224, 199, 0.61)",
      "sidebar_border": "rgb(248, 112, 140)",
      "sidebar_highlight_text": "rgb(90, 224, 199)",
      "sidebar_highlight": "rgba(248, 112, 140, 0.16)",
      "sidebar_text": "rgb(90, 224, 199)",
      "sidebar": "rgb(0, 0, 0)",
      "tab_loading": "rgb(90, 224, 199)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f71f22f5-db3f-43a0-9eb0-0af4b09e2e8e}"
    }
  }
}