Examine source code of Electric Eel

{
  "manifest_version": 2,
  "version": "1.3",
  "name": "Electric Eel",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(33, 42, 61)",
      "toolbar_text": "rgb(250, 247, 245)",
      "frame": "rgb(22, 29, 44)",
      "tab_background_text": "rgb(141, 144, 152)",
      "toolbar_field": "rgb(17, 22, 31)",
      "toolbar_field_text": "rgb(250, 247, 245)",
      "tab_line": "rgba(255, 255, 255, 0)",
      "popup": "rgb(33, 42, 61)",
      "popup_text": "rgb(250, 247, 255)",
      "popup_border": "rgba(255, 255, 255, 0)",
      "popup_highlight": "rgb(13, 102, 126)",
      "tab_text": "rgb(250, 247, 245)",
      "toolbar_bottom_separator": "rgba(255, 255, 255, 0)",
      "toolbar_field_border_focus": "rgb(0, 212, 250)",
      "toolbar_field_border": "rgba(255, 255, 255, 0)",
      "toolbar_field_highlight": "rgb(13, 102, 126)",
      "toolbar_top_separator": "rgba(255, 255, 255, 0)",
      "tab_loading": "rgba(255, 255, 255, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{17aed3e3-8db7-456e-a44b-67dc7266639b}"
    }
  }
}