Examine source code of Gimp

{
  "name": "Gimp",
  "manifest_version": 2,
  "version": "3.0",
  "theme": {
    "images": {
      "theme_frame": "gimp-3.png"
    },
    "colors": {
      "frame": "rgba(138, 138, 138, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(176, 173, 173, 0.52)",
      "bookmark_text": "rgba(26, 26, 26, 1)",
      "toolbar_field": "rgba(56, 56, 56, 0.56)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(195, 199, 76, 0.56)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{23a03e63-6a17-4b77-8e13-73ccbc51a24c}"
    }
  }
}