Examine source code of Blurple

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Blurple",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-009-f069b97f439938a011297c84464f0df6.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(114, 137, 218)",
      "toolbar_text": "rgb(30, 29, 18)",
      "frame": "rgb(142, 156, 243)",
      "tab_background_text": "rgb(30, 29, 18)",
      "toolbar_field": "rgb(142, 156, 243)",
      "toolbar_field_text": "rgb(30, 29, 18)",
      "tab_line": "rgb(30, 29, 18)",
      "popup": "rgb(142, 156, 243)",
      "popup_text": "rgb(30, 29, 18)",
      "tab_loading": "rgb(30, 29, 18)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{085d2570-ed83-42b4-b312-891f529fc7ff}"
    }
  }
}