Editor not working when tab block has 4 tabs

Hi,
I have a very strange issue.
Installed Kadence Blocks v1.4.7 on WordPress v5.1.1
1. Create a page, add a Tab Block, save as Draft
2. Exit Editor
3. Open page in Editor, add 1 tab (now 4 tabs in total), save Draft
4. Exit Editor
5. Open page in Editor — white screen issue —
To resolve the white screen issue, I found deactivating Kadence worked.
I repeated this on another WordPress site with a different Theme, same issue.
Are you able to repeat this?
If so any suggestions to resolve it?
thanks