Split Tab view freezes Dorico

Empty Dorico String orchestra template.
Quadcore i7 Mac Mini with SSD drives, 16GB RAM, Mac OS X 10.11.6

In the process of exploring the Create Tab Groups function - vertical and horizontal splits, Dorico becomes unresponsive when attempting to remove the split (No Split) either by control-clicking the tab, or selecting the command from the Window menu. Force Quit required.

Are others are having this issue?
No need for me to use this function right now

We are certainly aware of a problem that can occur when you use the context menu on the tab, which we are in the process of fixing, and expect this to be addressed in the first post-release update.

Thank you.