Examine source code of Marvel Zombies

{
  "name": "Marvel Zombies",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "marvel-zombie.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(101, 34, 24, 0.39)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(42, 25, 57, 0.68)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 191, 0, 0.8)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{ec11a5be-03a6-4aca-b6b5-590da8cb2e41}"
    }
  }
}