Examine source code of Elegant OLED Black Theme

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Elegant Black Theme",
  "description": "Tasteful OLED black theme for Firefox",
  "author": "nikkehtine",
  "homepage_url": "https://github.com/nikkehtine/firefox-elegant-black-theme",
  "theme": {
    "colors": {
      "frame": "black",
      "frame_inactive": "black",
      "toolbar": "black",
      "toolbar_text": "#ddd",
      "toolbar_bottom_separator": "transparent",
      "bookmark_text": "#ddd",
      "tab_background_text": "#ddd",
      "tab_text": "#eee",
      "tab_selected_text": "#fefefe",
      "tab_selected": "#181818",
      "tab_line": "transparent",
      "button_background_hover": "#222",
      "button_background_active": "#1b1b1b",
      "icons_attention": "#eee",
      "toolbar_field": "black",
      "toolbar_field_text": "#ddd",
      "toolbar_field_border": "transparent",
      "toolbar_field_highlight": "#3f3f3f",
      "toolbar_field_focus": "black",
      "toolbar_field_focus_text": "#eee",
      "popup": "black",
      "popup_highlight": "#2b2b2b",
      "popup_border": "#181818",
      "sidebar": "black",
      "sidebar_border": "#181818",
      "sidebar_highlight": "#2b2b2b",
      "sidebar_text": "#eee",
      "sidebar_highlight_text": "#eee",
      "ntp_background": "black",
      "ntp_text": "#eee",
      "ntp_card_background": "#181818"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{c8f7afb5-4e72-4bde-b982-e17143bc2d18}"
    }
  }
}