I gave this a thought for a moment. Since we're using a real browser, there are huge amount of different ways to get the browser display a file:// link. Redirect is one, window.location.href is another, etc. The service shouldn't be run publicly in the internet for real use cases. If you do, the server should be designed in a way that it's not dangerous if the web server user gets read access to file system. I added a warning about this in the top of the README.