Examine source code of Crimson Blue 2

{
  "manifest_version": 2,
  "name": "Crimson Blue",
  "version": "1.0",
  "description": "Blue and red browser theme.",
  "theme": {
    "colors": {
      "frame": "#0B3D91",
      "toolbar": "#1565C0",
      "toolbar_text": "#FFFFFF",
      "tab_background_text": "#FFFFFF",
      "bookmark_text": "#FFFFFF",
      "tab_line": "#E53935",
      "popup": "#1976D2",
      "popup_text": "#FFFFFF",
      "popup_highlight": "#E53935",
      "popup_highlight_text": "#FFFFFF",
      "icons": "#FFFFFF"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{15c95775-21ec-4f98-a109-03ea1393818c}"
    }
  }
}