Examine source code of Soultrap (stone theme)

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#4d4b4b",
      "tab_background_text": "#fcfcfc"
    }
  },
  "version": "2.0",
  "name": "Soultrap (stone theme)",
  "manifest_version": 2,
  "description": "Firefox theme for the Atlanta-based metal band, Soultrap."
}