Examine source code of Calming Voice

{
  "name": "Calming Voice",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Calming Voice.png"
    },
    "colors": {
      "frame": "rgba(30, 59, 41, 1)",
      "tab_background_text": "rgba(228, 225, 120, 1)",
      "toolbar": "rgba(31, 61, 43, 0)",
      "bookmark_text": "rgba(228, 225, 120, 1)",
      "toolbar_field": "rgba(31, 61, 43, 0)",
      "toolbar_field_text": "rgba(136, 209, 75, 1)",
      "tab_line": "rgba(240, 135, 173, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{0143dfc7-391c-43a3-a8d7-865cbb81e94e}"
    }
  }
}