Examine source code of Elemental Couple Fanmade

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Elemental Couple Fanmade",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(192, 8, 52)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(217, 9, 58)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(217, 9, 58)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(255, 255, 255)",
      "popup": "rgb(217, 9, 58)",
      "popup_text": "rgb(255, 255, 255)",
      "tab_loading": "rgb(255, 255, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{78ceece9-e707-4a5c-9ce0-75d365748e51}"
    }
  }
}