Examine source code of Industrial

{
  "manifest_version": 3,
  "version": "1.5",
  "name": "Industrial",
  "description": "High contrast industrial theme",
  "browser_specific_settings": {
    "gecko": {
      "id": "{230c67ae-c472-414e-bd94-5b926bee3f20}"
    }
  },
  "icons": {
    "48": "seismos.png",
    "96": "seismos@2x.png"
  },
  "theme": {
    "colors": {
      "toolbar": "#1A1A1A",
      "toolbar_text": "#FFD500",
      "frame": "#0D0D0D",
      "tab_background_text": "#FFD500",
      "toolbar_field": "#FFD500",
      "toolbar_field_text": "#0D0D0D",
      "tab_line": "#FF1744",
      "popup": "#1A1A1A",
      "popup_text": "#FFD500",
      "tab_selected": "#262626",
      "tab_text": "#FFD500",
      "tab_loading": "#FF1744",
      "popup_highlight": "#FFD500",
      "popup_highlight_text": "#0D0D0D",
      "sidebar": "#1A1A1A",
      "sidebar_text": "#FFD500",
      "tab_background_separator": "#3A3A3A"
    }
  }
}