If you configure a Turbo root as follows:

<meta name="turbo-root" content="/app">

Turbo Drive will handle navigations to URLs within that root (like /app/foo), but not navigations to the root itself (/app).

We can see why this happens by following the logic from the locationIsVisitable function:

1. locationIsVisitable is called
   • location = http://example.com/app
   • rootLocation = http://example.com/app
2. These are passed into isPrefixedBy, which via getPrefix, adds a trailing slash to the root URL:

// location -> baseURL, rootLocation -> url
export function isPrefixedBy(baseURL: URL, url: URL) {
  const prefix = getPrefix(url) // = http://example.com/app/
  return baseURL.href === expandURL(prefix).href || baseURL.href.startsWith(prefix)
}

4. Now the comparison is 'http://example.com/app' === 'http://example.com/app/' || 'http://example.com/app'.startsWith('http://example.com/app/'), which is false. No Turbo Drive.