the mails generated with mail merge wizard doesn't appear in the send directory

I sent a series of mails using LO Writer’s Mail Merge Wizard Tool but the sent mails do not appear in the sent directory of the sender’s mailbox, Is this the standard behavior of the mail merge tool?

I’m using LibreOffice on Open SUSE Tumbleweed on an old HP Compact 5800 Core2 duo 3GHz with 2 GB RAM.

The outgoing server configured in LO does not belong to the same account as my the inboxes (Gmail account), does this make a difference?