Examine source code of Levi - Attack on Titan

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#760a09",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Levi - Attack on Titan",
  "manifest_version": 2,
  "description": "Hooray. Now Levi gets to look sexy on your firefox browser! :D \nPlease note that I found this on ZeroChan, so I cannot properly credit the author. Please tell me if this your work, so I am able to credit it properly. \n\n-NyuNeon"
}