Examine source code of b1a4-twitter

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#fffff5",
      "tab_background_text": "#4c03a6"
    }
  },
  "version": "2.0",
  "name": "b1a4-twitter",
  "manifest_version": 2
}