Examine source code of refined-azure

{
  "manifest_version": 2,
  "name": "refined-azure",
  "author": "Darcy Clarke <darcy@darcyclarke.me>",
  "description": "A custom theme to the portal.azure.com site",
  "version": "0.0.2",
  "homepage_url": "https://github.com/darcyclarke/refined-azure",
  "incognito": "spanning",
  "icons": {
    "16": "icons/icon-16.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "browser_action": {
    "default_icon": "icons/icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://portal.azure.com/*"
      ],
      "run_at": "document_start",
      "css": [
        "theme.css"
      ],
      "js": [
        "theme.js"
      ]
    }
  ],
  "permissions": [
    "activeTab"
  ]
}