Invalid access to memory - @@Synchronizecontroller@Finalize

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<If relevant, consider attaching a session log file or a screenshot)>

WinSCP 5.19.5

Error message:
Invalid access to memory.

Stack trace:
(00CD1A7B)
(00FC4482)
(00FC64EA)
(00FC32A4)
(000879EF) ntdll.dll
(00073EE1) ntdll.dll.KiUserExceptionDispatcher
(00CCB168)
(00CCB19F)
(00CBDC5F)
(00DC0873)
(000AF3C2) @@Synchronizecontroller@Finalize
(000B0BB5)
(000AFFBB)
(000B05DF)
(000B0F01)
(000B0C4E)
(00020EE2)
(00020E5A)
(000B0C4E)
(000AFFBB)
(002803E1)
(0027FA28)
(003C7B64)
(0003FF19) USER32.dll
(00036EC5) USER32.dll
(000365A2) USER32.dll
(00034746) USER32.dll.CallWindowProcW
(0049E76B)
(003C7B64)
(0003FF19) USER32.dll
(00036EC5) USER32.dll
(00034C35) USER32.dll
(000349FB) USER32.dll.DispatchMessageW

(00CD1A7B)
(000879EF) ntdll.dll
(00073EE1) ntdll.dll.KiUserExceptionDispatcher
(00CCB168)
(00CCB19F)
(00CBDC5F)
(00DC0873)
(000AF3C2) @@Synchronizecontroller@Finalize
(000B0BB5)
(000AFFBB)
(000B05DF)
(000B0F01)
(000B0C4E)
(00020EE2)
(00020E5A)
(000B0C4E)
(000AFFBB)
(002803E1)
(0027FA28)
(003C7B64)
(0003FF19) USER32.dll
(00036EC5) USER32.dll
(000365A2) USER32.dll
(00034746) USER32.dll.CallWindowProcW
(0049E76B)
(003C7B64)
(0003FF19) USER32.dll
(00036EC5) USER32.dll
(00034C35) USER32.dll
(000349FB) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.