Examine source code of Swamp Train

{
  "theme": {
    "images": {
      "theme_frame": "swamp-train-header.png"
    },
    "colors": {
      "frame": "#bababa",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Swamp Train",
  "manifest_version": 2,
  "description": "A black and white design with a steam locomotive emerging from a black background. Has the words: Swamp Train, Cigar Box Guitar Blues.\nA persona made for the blues band I play in."
}