Examine source code of Regret

{
  "theme": {
    "images": {
      "theme_frame": "Regret-Header.jpg"
    },
    "colors": {
      "frame": "#e9980b",
      "tab_background_text": "#e9980b"
    }
  },
  "version": "2.0",
  "name": "Regret",
  "manifest_version": 2
}