Zones Tab in Main Mixer window broken?

I have installed Cubase 11 Pro
The ‘zones’ tab in bottom of the left side panel no longer appears to function.
I cannot create new left, centre and right hand zones in the mixer.
This appears to have effected the ‘zones’ function in 10.5 as my old projects have not retained their ‘zones’ in the main mixer panel. This happens in both Cubase 10.5 and 11.
Is this a bug ?
Or am I missing someway of activating the zones function ?


It works for me here.

Could you try in Cubase Safe Start Mode [Disable preferences], please?