Examine source code of Full-on Black

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Full-on Black",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(0, 0, 0)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(93, 93, 93)",
      "toolbar_field": "rgb(17, 17, 17)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(255, 255, 255)",
      "popup": "rgb(9, 9, 9)",
      "popup_text": "rgb(255, 255, 255)",
      "tab_loading": "rgb(255, 255, 255)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{46761e43-4839-4833-ae36-712d758dcc1f}"
    }
  }
}