<Try to describe precise steps that lead to the problem (where do you click, what keys do you press, what do you see, etc.)>
<If relevant, consider attaching a session log file or a screenshot)>

WinSCP 5.15.3

Error message:
Zugriffsverletzung - ungültiger Zugriff auf den Speicher.

Stack trace:
(FFFFF118)
(0003EF0E) ntdll.dll.ZwWow64CallFunction64
(0003F68A) ntdll.dll.KiUserExceptionDispatcher

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.