Examine source code of Bookish

{
  "name": "Bookish",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "1capture.png"
    },
    "colors": {
      "frame": "rgba(87, 69, 63, 1)",
      "tab_background_text": "rgba(150, 131, 120, 1)",
      "toolbar": "rgba(56, 47, 43, 1)",
      "bookmark_text": "rgba(150, 131, 120, 1)",
      "toolbar_field": "rgba(87, 69, 63, 1)",
      "toolbar_field_text": "rgba(150, 131, 120, 1)"
    }
  }
}