Examine source code of Space Traveling

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Space Traveler",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(53, 0, 100, 0.57)",
      "toolbar_text": "rgb(0, 240, 255)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(64, 77, 255)",
      "toolbar_field": "rgba(0, 71, 151, 0.21)",
      "toolbar_field_text": "rgb(255, 111, 167)",
      "tab_line": "rgb(0, 134, 255)",
      "popup": "rgba(10, 0, 33, 0.89)",
      "popup_text": "rgb(0, 231, 255)",
      "button_background_hover": "rgba(255, 27, 178, 0.24)",
      "icons_attention": "rgb(255, 95, 192)",
      "icons": "rgba(0, 216, 255, 0.84)",
      "ntp_background": "rgb(8, 2, 26)",
      "ntp_text": "rgba(0, 217, 255, 0.84)",
      "popup_border": "rgb(142, 29, 255)",
      "sidebar_border": "rgb(79, 0, 188)",
      "sidebar_highlight": "rgba(255, 0, 193, 0.32)",
      "sidebar_text": "rgb(0, 248, 255)",
      "sidebar": "rgb(18, 0, 44)",
      "tab_selected": "rgba(0, 204, 245, 0.18)",
      "tab_loading": "rgb(0, 134, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{b1f9f3ff-7403-4ae0-8ecd-6cf918f5ee55}"
    }
  }
}