Examine source code of TooDown

{
  "name": "TooDown",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "20180328_103640.jpg"
    },
    "colors": {
      "toolbar": "rgba(48, 32, 224, 1)",
      "toolbar_field": "rgba(45, 16, 230, 1)",
      "toolbar_field_text": "rgba(240, 51, 51, 1)",
      "frame": "rgba(227, 13, 56, 1)",
      "tab_background_text": "rgba(103, 191, 235, 1)",
      "bookmark_text": "rgba(109, 231, 237, 1)"
    }
  }
}