Error reading ImageList144.PngImages: Invalid ImageList - __tpdsc__ System::Generics::Defaults::IComparer__1<System::TObject *>

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WinSCP 6.3.3

Error message:
Error reading ImageList144.PngImages: Invalid ImageList

Stack trace:
(003567E2) __tpdsc__ System::Generics::Defaults::IComparer__1<System::TObject *>
(003564AE) __tpdsc__ System::Generics::Collections::TThreadList__1<System::DelphiInterface<System::IInterface> >
(00528FC3) CFtpControlSocket::List
(002181BB) Vcl::Forms::TCustomForm::SetActiveControl
(00217CEE) Vcl::Forms::TCustomForm::CreateWnd
(00217541) Vcl::Forms::TCustomForm::SetWindowToMonitor
(00217523) Vcl::Forms::TCustomForm::SetWindowToMonitor
(0022519D) Vcl::Forms::TFormStyleHook::TMainMenuBarStyleHook::DrawItem
(002175B5) Vcl::Forms::_16691
(002174F4) Vcl::Forms::TCustomForm::SetWindowToMonitor
(0022519D) Vcl::Forms::TFormStyleHook::TMainMenuBarStyleHook::DrawItem
(003C2981) System::Actions::TContainedActionList::SameCategory
(00D05E5C)
(0021239A) __tpdsc__ Vcl::Forms::TFormStyleHook
(00207DDF) Vcl::Graphics::initialization
(00209733) Vcl::Forms::TCustomFrame::
(002097C1) Vcl::Forms::TCustomFrame::
(003C217A) System::Actions::TContainedAction::SetGroupIndex
(00005912) TCustomScpExplorerForm::CommandLineFromAnotherInstance
(00CFF8E7)
(0000B8F0) std::length_error::length_error
(0000BA94) std::length_error::length_error
(0005C9D6) Console
(0000BDFE) std::basic_string<char, std::char_traits<char>, std::allocator<char> >::_Tidy
(000C423A) TCustomCommandType::LoadExtension
(00B390BC)
(00C68863)
(00C687D9)
(00C68982)
(00C69C38)
(000192D1) TCustomScpExplorerForm::DoSynchronizeInvalid
(00012AEA) TCustomScpExplorerForm::ExecuteFile
(00012B9E) TCustomScpExplorerForm::ExecuteFile
(00012DD8) TCustomScpExplorerForm::ExecuteFile
(00012F97) TCustomScpExplorerForm::ExecuteFile
(0004F0F6) TConsoleRunner::ScriptTerminalQueryUser
(00275A24) __tpdsc__ Vcl::Comctrls::TRichEdit
(00359965) __tpdsc__ System::Generics::Collections::TCollectionNotifyEvent__1<System::Classes::TBasicActionLink *>
(002271BC) Vcl::Forms::TFormStyleHook::GetMDIScrollInfo
(00040819) USER32.dll
(00036F65) USER32.dll
(0003589C) USER32.dll
(000353BB) USER32.dll.DispatchMessageW

(00217B13) Vcl::Forms::TCustomForm::CreateParams
(00217D4D) Vcl::Forms::TCustomForm::CreateWnd
(00217541) Vcl::Forms::TCustomForm::SetWindowToMonitor
(00217523) Vcl::Forms::TCustomForm::SetWindowToMonitor
(0022519D) Vcl::Forms::TFormStyleHook::TMainMenuBarStyleHook::DrawItem
(002175B5) Vcl::Forms::_16691
(002174F4) Vcl::Forms::TCustomForm::SetWindowToMonitor
(0022519D) Vcl::Forms::TFormStyleHook::TMainMenuBarStyleHook::DrawItem
(003C2981) System::Actions::TContainedActionList::SameCategory
(00D05E5C)
(0021239A) __tpdsc__ Vcl::Forms::TFormStyleHook
(00207DDF) Vcl::Graphics::initialization
(00209733) Vcl::Forms::TCustomFrame::
(002097C1) Vcl::Forms::TCustomFrame::
(003C217A) System::Actions::TContainedAction::SetGroupIndex
(00005912) TCustomScpExplorerForm::CommandLineFromAnotherInstance
%0

The problem happens rarely. I cannot reproduce it.