Invalid access to memory

<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 5.19.1

Error message:
Invalid access to memory.

Stack trace:
(00283063)
(0008788F) ntdll.dll
(00073EC1) ntdll.dll.KiUserExceptionDispatcher
(0046EA89)
(0046EA89)
(0046EA89)
(0046EB18)
(0048106E)
(0046E7A9)
(00256CD3)
(003C79CC)
(0003DEB9) USER32.dll
(00034E75) USER32.dll
(00032BE5) USER32.dll
(000329AB) USER32.dll.DispatchMessageW

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.