We upgraded from Scheduler Pro 5.3.5 to 5.6.8, and we are having an issue with the scheduler freezing the entire browser window after event creation. I have created a demo app, and was able to repro the problem.
Steps to repro:
Double click scheduler timeline, and click save to create a new event.
Shift back a week, and then try to shift forward a week
At this point the entire app will be unresponsive. You are also unable to open dev tools. It crashes the whole browser instance.
Thanks for the bug report, I believe this is the same issue as one we had reported recently. https://github.com/bryntum/support/issues/8866. Here's a link to that forum post also: viewtopic.php?t=28418&start=10. Ghous noticed that it happens when a Date is used inside useState (as there is in your code too). I'm investigating it to find the reason for this. Please subscribe to the github issue to get more updates about this.
The error is due to loading columns config multiple times. Your app has columns config both in props, and in the configToUse variable. If you remove it from the props, just keep it in configToUse the problem goes away. If you want to make changes to the config, please put it inside useState also as in this example: https://bryntum.com/products/scheduler/examples/frameworks/react/javascript/react-events/build/ (Check the code for it in your download from customer zone's example folder: Scheduler\examples\frameworks\react\javascript\react-events)
Also, please avoid using the config prop, instead pass the config directly like this: