refactorings in LPEX are saved automatically and the undo stack is lost

refactorings in LPEX are saved automatically and the undo stack is lost.
Cobol Editor
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1) add one line like DISPLAY "one of the pgm's fields".
2) Highlight a paragraph name right click -> refactor -> Rename
and rename.
3) close without saving -> the editor will ask you wether you want to
save or not
4) do not save, then reopen the pgm
None of the changes have been saved

Redo 1) 2) 3), then save, then reopen.
both changes have been saved

LPEX
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Do 1) 2) 3); The program will close without asking: do you want to save?
because Save has been already done.
.
Customer would like LPEX to work like Cobol Editor.