Examine source code of MAJKASSAB - Rosa

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Rosa",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-011-d53e0d0d1538ed554a90e056a2f04eca.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(245, 194, 197)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(111, 14, 21)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(251, 221, 221)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgba(0, 0, 0, 0.57)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(0, 0, 0)",
      "tab_loading": "rgba(0, 0, 0, 0.57)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{49e73f76-40c4-488a-aeea-9c02be57fa68}"
    }
  }
}