Control '' has no parent window

<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 5.7

Error message:
Control '' has no parent window

Stack trace:
[0127B260] Vcl::Controls::TWinControl::CreateWnd
[011E139B] Vcl::Stdctrls::TCustomEdit::CreateWnd
[012B8A80] Vcl::Comctrls::TCustomRichEdit::CreateWnd
[0127B7E6] Vcl::Controls::TWinControl::CreateHandle

Thanks for your report.
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