Examine source code of Negative_Breadboard

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#f2f2ea",
      "tab_background_text": "#0c1b42"
    }
  },
  "version": "2.0",
  "name": "Negative_Breadboard",
  "manifest_version": 2,
  "description": "Negative Breadboard (white) pattern based upon the printed circuit board theme."
}