I have the same problem as here https://www.odoo.com/fr_FR/forum/aide-1/question/how-to-avoid-the-selected-account-of-your-journal-entry-forces-to-provide-a-secondary-currency-108966
and can "lettrer" my accounting.
I'm unable to find anything close to what is described on link above... In Accounting > Configuration > Journals
I can select any journal and try to edit it there is now where to find a currency setting... and if I try authorize "lettrage" it doesn't solve anything...
This is crazy stupid, I can't find any solution to this :( please help me.
Did you activate the developer mode?