Examine source code of 13th c. Battle

{
  "name": "13th c. Battle",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "Maj.Bib.jpg"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 0)",
      "tab_background_text": "rgba(0, 0, 0, 1)",
      "toolbar": "rgba(163, 116, 59, 0.54)",
      "bookmark_text": "rgba(0, 0, 0, 1)",
      "toolbar_field": "rgba(112, 165, 199, 0.4)",
      "toolbar_field_text": "rgba(3, 3, 3, 1)",
      "tab_line": "rgba(69, 69, 69, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{51e55fb3-067e-4922-874e-9ac738e6d25b}"
    }
  }
}