Examine source code of YES Aurora cover

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "YES Aurora-readable",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png",
        "images/1.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top",
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat",
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(19, 12, 47)",
      "toolbar_text": "rgb(101, 227, 199)",
      "frame": "rgb(32, 30, 70)",
      "tab_background_text": "rgb(219, 225, 198)",
      "toolbar_field": "rgb(50, 55, 79)",
      "toolbar_field_text": "rgb(225, 175, 190)",
      "tab_line": "rgb(219, 80, 104)",
      "popup": "rgb(47, 20, 98)",
      "popup_text": "rgb(229, 111, 206)",
      "button_background_hover": "rgba(61, 81, 101, 0.89)",
      "ntp_background": "rgba(40, 46, 62, 0.64)",
      "popup_border": "rgba(225, 128, 183, 0.89)",
      "tab_background_separator": "rgba(227, 106, 12, 0.53)",
      "tab_loading": "rgb(219, 80, 104)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{022d9e76-9965-47a8-bfbf-66c7d84e579b}"
    }
  }
}