[plt-scheme] problem with browser module

When I run this:

#lang scheme
(require browser)

I get this error:

m: argument does not implement #<|interface:hyper-frame<%>|>:
#<class:...ork/private/frame.ss:316:4>

What does the error mean?  Is the browser module broken?  I'm
completely new to Scheme, so I don't understand what's going on here.