Steps to reproduce:
If you update the config in the example and set modal: false, the issue does not happen.
I couldn't reproduce in latest versions of Safari or Firefox.
Hey aaronf,
Thanks for reaching out and welcome to our forums. 
I tried to follow the steps that you mentioned, but everything worked as expected on Chrome. I attached a video that you can verify, could you please confirm that I tried to reproduce it in the right way?
Thanks for the fast reply Marcio!
Your steps are correct.
It looks like this may be fixed in the latest version of Chrome! I confirmed that it crashes on 126.0.6478.183, but upgrading to the latest version 127.0.6533.89 fixes the issue.
I can probably get you a video of the crash if you are still interested. However, this seems like a browser issue and not a Bryntum issue.
Hey aaronf,
I don't think it's necessary for the video, as you mentioned that the steps are correct.
We'll keep an eye out if there are more reports, but as you said, it seems a Chrome issue.
Glad that is all working now. If you need any assistance please don't hesitate to contact us here.