Examine source code of MiniFire

{
  "manifest_version": 2,
  "version": "1.2",
  "name": "Minifire",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(255, 255, 255)",
      "toolbar_text": "rgba(0, 0, 0, 0.75)",
      "frame": "rgb(52, 56, 66)",
      "tab_background_text": "rgb(191, 196, 211)",
      "toolbar_field": "rgba(83, 106, 157, 0.01)",
      "toolbar_field_text": "rgba(22, 26, 34, 0.57)",
      "tab_line": "rgb(68, 74, 87)",
      "popup": "rgb(255, 255, 255)",
      "popup_text": "rgba(0, 0, 0, 0.84)",
      "popup_border": "rgba(0, 0, 0, 0.21)",
      "sidebar_border": "rgba(0, 0, 0, 0.41)",
      "tab_loading": "rgb(0, 124, 255)",
      "tab_selected": "rgb(255, 255, 255)",
      "toolbar_bottom_separator": "rgb(223, 223, 223)",
      "toolbar_field_border_focus": "rgba(154, 154, 154, 0.23)",
      "toolbar_field_border": "rgba(102, 130, 154, 0.09)",
      "toolbar_field_focus": "rgb(255, 255, 255)"
    }
  }
}