Examine source code of just

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "just",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(0, 53, 85)",
      "toolbar_text": "rgb(248, 112, 140)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(77, 244, 0)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(255, 158, 0)",
      "tab_line": "rgb(253, 194, 0)",
      "popup": "rgb(0, 0, 0)",
      "popup_text": "rgb(234, 214, 0)",
      "button_background_active": "rgb(44, 50, 55)",
      "button_background_hover": "rgb(7, 7, 7)",
      "frame_inactive": "rgb(47, 117, 171)",
      "icons_attention": "rgb(220, 202, 21)",
      "icons": "rgb(12, 235, 53)",
      "ntp_background": "rgb(49, 70, 84)",
      "ntp_text": "rgb(0, 0, 0)",
      "popup_highlight_text": "rgb(228, 169, 0)",
      "sidebar_border": "rgb(105, 118, 126)",
      "sidebar_highlight_text": "rgb(35, 139, 205)",
      "sidebar_highlight": "rgb(27, 145, 219)",
      "sidebar_text": "rgb(33, 143, 212)",
      "tab_background_separator": "rgb(47, 47, 49)",
      "tab_loading": "rgb(0, 0, 0)",
      "tab_selected": "rgb(234, 214, 0)",
      "tab_text": "rgb(8, 8, 8)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ac035055-9ca5-4445-b607-eccc19cc4909}"
    }
  }
}