Examine source code of Gengar Animated v2

{
  "name": "Gengar Animated",
  "author": "LEX",
  "manifest_version": 2,
  "version": "20250905.0",
  "theme": {
    "colors": {
      "frame": "rgb(62, 8, 104)",
      "frame_inactive": "rgb(62, 8, 104)",
      "tab_text": "rgb(255, 255, 255)",
      "tab_background_text": "rgb(190, 190, 250)",
      "tab_background_separator": "rgba(255, 255, 255, 0.5)",
      "tab_line": "#3e0868",
      "tab_loading": "#d10028",
      "icons_attention": "#d10028",
      "toolbar": "rgba(32, 32, 32, 0.25)",
      "toolbar_top_separator": "rgba(32, 32, 32, 0.25)",
      "toolbar_bottom_separator": "rgba(32, 32, 32, .25)",
      "toolbar_vertical_separator": "rgba(170, 170, 170, 0.25)",
      "toolbar_field": "rgb(18, 18, 18)",
      "toolbar_field_text": "rgb(200, 200, 200)",
      "toolbar_field_border": "rgb(18, 18, 18)",
      "toolbar_field_focus": "rgb(18, 18, 18)",
      "toolbar_field_border_focus": "rgb(30, 30, 30)",
      "button_background_hover": "rgba(133, 133, 133, 0.25)",
      "button_background_active": "rgba(200, 200, 200, 0.25)",
      "icons": "rgb(200, 200, 200)",
      "bookmark_text": "rgb(170, 170, 170)",
      "popup": "rgb(18, 18, 18)",
      "popup_text": "rgb(200, 200, 200)",
      "popup_border": "rgb(18, 18, 18)",
      "popup_highlight": "#21252B",
      "popup_highlight_text": "rgb(255, 255, 255)",
      "ntp_background": "rgb(18, 18, 18)",
      "ntp_text": "rgb(170, 170, 170)",
      "sidebar": "rgb(32, 32, 32)",
      "sidebar_text": "rgb(170, 170, 170)",
      "sidebar_border": "rgb(18, 18, 18)",
      "sidebar_highlight": "#21252b",
      "sidebar_highlight_text": "rgb(170, 170, 170)"
    },
    "images": {
      "additional_backgrounds": [
        "Gengar.gif",
        "Gengar2.gif"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top",
        "left top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat",
        "no-repeat"
      ],
      "additional_backgrounds_position": "calc(100% - 10px) 10px, 10px 10px"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "gengar-animated-2@lex",
      "strict_min_version": "109.0"
    }
  }
}