Duplicate card and object command lc 9.0.4

[Muaadh Salih]

Until now I was using LC 7.1..4 with very few ( solvable ) problems.
I installed the latest version (9.0.4) and noticed that  "Duplicate Card "
command , form either line command or menu click produced nothing . .
I know I can use copy and paste  but this requires reediting existing
stacks  with , sometime , unwanted problem.
This issue concerns "duplicate  Card" only . It works fine for duplicating
  other stack object.
I have removed old preference fines and this installation is a clean one.
but still can not duplicate card .
His this command being disabled in 9.0.4 ?
We are putting up a course module in "programming for humanities " degree
and want student to be confident on what they are using .
Thanks for the help

Muaadh
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