Examine source code of Journal Tabs

{
  "manifest_version": 2,
  "name": "New Tabs - Random Oncology Journals",
  "version": "1.0",
  "description": "Loads a random URL when a new tab is opened.",
  "chrome_url_overrides": {
    "newtab": "index.html"
  },
  "permissions": [
    "tabs"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{886f26ae-6314-482a-8765-cc82442a14ab}"
    }
  }
}