DrRacket Internal Error

[AlexKnauth]

I'm not sure whether this is a problem with DrRacket or Optimization Coach, but I'm getting errors like this when I click the Optimization Coach button:

sequence-contract-violation: negative: method set-max-width cannot be called, except in states (unlocked write-lock), args 1701
  context...:
   .../racket/collects/racket/private/more-scheme.rkt:148:2: call-with-break-parameterization
   .../racket/share/pkgs/gui-lib/mred/private/lock.rkt:43:38
   .../racket/collects/ffi/unsafe/atomic.rkt:73:13
   .../racket/collects/racket/private/more-scheme.rkt:148:2: call-with-break-parameterization
   .../racket/collects/racket/private/map.rkt:267:2: gen-for-each
   [repeats 26 more times]
   .../racket/share/pkgs/gui-lib/mred/private/wxpanel.rkt:193:8: change-children method in wx-make-basic-panel%
   .../racket/collects/ffi/unsafe/atomic.rkt:73:13
   .../racket/share/pkgs/optimization-coach/optimization-coach/tool.rkt:422:6: close-optimization-coach method in frame-mixin
   .../racket/share/pkgs/optimization-coach/optimization-coach/tool.rkt:399:19: with-handlers-handler752
   .../racket/collects/racket/private/more-scheme.rkt:163:2: select-handler/no-breaks
   .../racket/share/pkgs/optimization-coach/optimization-coach/tool.rkt:395:11

This is on Racket version 8.9.0.3--2023-04-25.