Out of memory when viewing server log file

<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 5.6.4

Error message:
Out of memory

Stack trace:
[00C31EFE] System::__linkproc__ NewUnicodeString
[00C31EFE] System::__linkproc__ NewUnicodeString
[00BBEE27] System::Classes::TComponent::UpdateAction
[00A5BDF8] Vcl::Forms::TCustomForm::CMActionUpdate
[00A97591] Vcl::Controls::TControl::WndProc
[00A9C0D5] Vcl::Controls::TWinControl::WndProc
[00A56E78] Vcl::Forms::TCustomForm::WndProc
[01007051] Vclcommon::C2442_0
[00A971CC] Vcl::Controls::TControl::Perform
[00A6202F] Vcl::Forms::TApplication::DispatchAction
[00BBFFF8] System::Classes::_18201
[75D162F7] USER32.dll
[75D16D35] USER32.dll
[75D16DE3] USER32.dll
[75D16E41] USER32.dll
[77150107] ntdll.dll.KiUserCallbackDispatcher
[75D196C0] USER32.dll.SendMessageW
[00A923D8] Vcl::Controls::SendAppMessage
[00CA4FE2] Tb2item::TTBPopupMenu::IsShortCut

Thanks for your report.
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