Out of 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 6.3.4

Error message:
Out of memory

Stack trace:
(0016D785)
(0016D785)
(0015D9D3)
(0015D571)
(001550CC)
(00156578)
(001531B7)
(00CE5F0E)
(00CE8241)
(00107427)
(00107D30)
(00107F7E)
(00109BAC)
(000D39B9)
(00025DA8)
(000C3E41)
(00C61A74)
(003CD06A)
(0011C0F6)
(000031E3)
(00E20B11)
(00066C5B) ntdll.dll.RtlGetAppContainerNamedObjectPath
(00066C28) ntdll.dll.RtlGetAppContainerNamedObjectPath

Status: unknown_rel_addr

The problem happens rarely. I cannot reproduce it.