Examine source code of Just Idk

{
  "name": "xd",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "xd.png"
    },
    "colors": {
      "frame": "rgba(50, 79, 138, 1)",
      "tab_background_text": "rgba(255, 255, 255, 0.53)",
      "toolbar": "rgba(132, 139, 196, 1)",
      "bookmark_text": "rgba(196, 200, 230, 1)",
      "toolbar_field": "rgba(169, 174, 217, 1)",
      "toolbar_field_text": "rgba(219, 219, 219, 0.77)"
    }
  }
}