Examine source code of Arithmetic

{
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    "images": {
      "theme_frame": "mathheader.jpg"
    },
    "colors": {
      "frame": "#fff700",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Arithmetic",
  "manifest_version": 2,
  "description": "For all the math wizards."
}