Examine source code of 2015 theme Like

{
  "name": "Screenshot 2025-07-29 at 12.48.23 PM",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "Screenshot 2025-07-29 at 12.54.48 PM.png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(0, 0, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{a24df499-e7dd-441d-b3f0-a79def355830}"
    }
  }
}