Hi,
Thanks for letting me know that it is something related to ScrollButtons feature. I have created a ticket to fix this issue here https://github.com/bryntum/support/issues/8895. You can subscribe to it to keep track of updates. Not sure about its affects but you can try checking the basic functionalities like timeline events are fired etc. Probably you can use this as a workaround untill the fix is released for this issue.
Thanks for your patience.
Regards,
Ghous
