remove 'AADL [...]', using 'Sheets and Objects' dialog

[Carl Karsten <carl personnelware com>]

I upgraded to v.97, and now when I run dia I get:

The system sheet 'AADL' appears to be more recent than your custom
version and has been loaded as 'AADL [Copy of system]' for this session.
Move new objects (if any) from 'AADL [Copy of system]' into your custom sheet
or remove 'AADL [Copy of system]', using the 'Sheets and Objects' dialog.

I only added one object, and I don't use it, so I don't really care if
it goes away.  I can't figure out how to do the 2nd option: "remove
'AADL [Copy of system]', using the 'Sheets and Objects' dialog."

I see an option to remove one object, but not the whole sheet.

-- 
Carl K