Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

<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 5.15.7

Error message:
Invalid access to memory.

Stack trace:
(000ABDFE) TTerminalManager::ShouldDisplayQueueStatusOnAppTitle
(0006246E) ntdll.dll
(0000F12E) ntdll.dll.KiUserExceptionDispatcher
(00025260) TCustomScpExplorerForm::UpdateControls
(0004C227) TScpCommanderForm::DoShow
(0002748F) TCustomScpExplorerForm::CMShowingChanged
(0002731E) TCustomScpExplorerForm::Dispatch
(002791FD) Vcl::Controls::TWinControl::WndProc
(002336C4) Vcl::Forms::TCustomForm::WndProc
(008C61D8) Vclcommon::C2842_0

(FFFFF004)WinSCP.exe
(0006246E) ntdll.dll
(0000F12E) ntdll.dll.KiUserExceptionDispatcher
(00025260) TCustomScpExplorerForm::UpdateControls
(0004C227) TScpCommanderForm::DoShow
(0002748F) TCustomScpExplorerForm::CMShowingChanged
(0002731E) TCustomScpExplorerForm::Dispatch
(002791FD) Vcl::Controls::TWinControl::WndProc
(002336C4) Vcl::Forms::TCustomForm::WndProc
(008C61D8) Vclcommon::C2842_0

I know how to reproduce the problem or the problem happens frequently enough. I wish to be contacted by the WinSCP team to help resolving the problem.