[GNC] retained earnings between two different financial periods

[mc]

Config:
gnucash 3.5 clean install.
(X)ubuntu Linux 18.04
gnucash files saved as sqlite.

Hi

I am new to gnucash and testing it.
Most things I have tried work as expected (and extremely well ;-)  )

One question: on the page:
www.gnucash.org/docs/v3/C/gnucash-help/tool-close-book.html 
<https://www.gnucash.org/docs/v3/C/gnucash-help/tool-close-book.html>
it states:
"GnuCash’s built-in reports automatically handle concepts
like retained earnings between two different financial periods"

However when I tested it
gnucash does NOT appear to separate retained earnings
between two different financial periods.

When I print a balance sheet report,
without closing the books,
I just get 1 net retained earnings number:
     Retained Earnings / Retained Losses
that includes the amounts from previous years.

The P&L for different years works as expected.

(after closing the books, the BS report also works as expected)

What have I missed?

thanks

mc