Examine source code of steak

{
  "name": "steak",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "AS001398_00.gif"
    },
    "colors": {
      "frame": "rgba(144, 157, 189, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{154f7d86-2b59-43a9-9df0-2b9c4c2439c0}"
    }
  }
}