https://bugs.winehq.org/show_bug.cgi?id=40446
--- Comment #5 from Artem S. Tashkinov t.artem@mailcity.com --- (In reply to rebe from comment #4)
Source code of WinSCP is available btw. https://winscp.net/download/WinSCP-5.11.3-Source.zip
Still an issue under a current Wine?
Yes.
Instead of the help message it says "Cannot display".