In the Import Bills & Invoices function:
- the user chooses the option 'Open not yet posted documents in tabs';
- the import file contains invoices that have a value for date_posted, so the system will attempt to post these invoices;
- but the invoices cannot be posted because of an issue with e.g. non existent account_posted;

In this case the system will not open a tab for the invoice, even though it is not yet posted.

In line 839 of dialog-bi-import.c, the code only checks if date_posted has a value, but not if the invoice has actually been posted.

836         // open new bill / invoice in a tab, if requested
837         if (g_ascii_strcasecmp(open_mode, "ALL") == 0
838                 || (g_ascii_strcasecmp(open_mode, "NOT_POSTED") == 0
839                     && strlen(date_posted) == 0))
840         {   
841             iw =  gnc_ui_invoice_edit (parent, invoice);
842             gnc_plugin_page_invoice_new (iw);
843         }