Examine source code of 28 Reasons

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "28 Reasons",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-008-60d2718f8c915b5ba09f31df5555b459.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(0, 0, 0)",
      "toolbar_text": "rgb(248, 112, 140)",
      "frame": "rgb(110, 8, 16)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(255, 2, 7)",
      "tab_line": "rgb(253, 2, 53)",
      "popup": "rgb(0, 0, 0)",
      "popup_text": "rgb(255, 0, 3)",
      "tab_loading": "rgb(253, 2, 53)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{f2fd41d6-8c1c-43ec-9d57-55956481caca}"
    }
  }
}