Hello, Oksana,

The provided video is greatly appreciated. I was able to reproduce the problem locally and confirm there is an issue with autocorrect words when scrolling in the spell-checker. I have logged it in our feedback portal by making this thread public. You can track its progress, subscribe for status changes and add your comments on the following link - feedback item.

I have also updated your Telerik Points.

Currently, due to the specifics of the issue, I can not suggest a workaround for this.

Let me know if you have other questions.

Regards,
Nadya
Progress Telerik