Examine source code of Simple-Marvel

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Simple-Marvel",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(255, 255, 255, 0.53)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(219, 5, 5)",
      "tab_background_text": "rgb(66, 64, 64)",
      "toolbar_field": "rgba(255, 255, 255, 0.53)",
      "toolbar_field_text": "rgb(0, 0, 0)",
      "tab_line": "rgb(248, 112, 140)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgb(0, 0, 0)",
      "tab_loading": "rgb(248, 112, 140)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dec41817-13c9-4fcc-89db-92ecd48edb2e}"
    }
  }
}