Examine source code of Space Apocalypse

{
  "name": "Space Apocalypse",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "burning-space-2.png"
    },
    "colors": {
      "frame": "rgba(156, 73, 0, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(128, 64, 0, 0.28)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(3, 3, 3, 0.32)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 89, 0, 0.5)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{efcaa67a-5daf-4da9-8afb-547491f75d76}"
    }
  }
}