Examine source code of New Empty Coloured Tab

{
  "name": "New Empty Coloured Tab",
  "description": "When you open a 'New Tab' it's blank and set to the background color of your desire.",
  "version": "1.5.2resigned1",
  "background": {
    "scripts": [
      "JS/GETbg.js"
    ]
  },
  "permissions": [
    "storage",
    "management"
  ],
  "icons": {
    "16": "icon_16.png",
    "48": "icon_48.png",
    "128": "icon_128.png"
  },
  "browser_action": {
    "default_icon": "icon_48.png",
    "default_popup": "popup.html"
  },
  "applications": {
    "gecko": {
      "id": "NewEmptyColouredTab@sonej",
      "strict_min_version": "57.0"
    }
  },
  "chrome_url_overrides": {
    "newtab": "enct.html"
  },
  "manifest_version": 2
}