Examine source code of shell casings

{
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    "images": {
      "theme_frame": "golden-bullets-wallpapers_10042_1152x864.jpg"
    },
    "colors": {
      "frame": "#030303",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "shell casings",
  "manifest_version": 2
}