Dual View Issue When Closing

After the latest update to Directory Opus I seem to be having an issue with closing a Dual Horizontal session. Basically when I exit DO I click the 'X" in the Upper Right corner of DO. With the dual view on I click the Red 'X" and it only closes the Dual View and I now have a single view. I have to click the 'X' a second time to actually close DO. This is strange and it did start until the last update.

Do you think this is a small bug?

Turn off Preferences / Folder Tabs / Options / Lister close button closes active tab

Thank you, that worked. So many options to choose from for sure. The last update must have turned this on some how.