List index out of bounds (0) - UnixExtractCommonPath

<Try to describe precise steps that lead to the problem (where do you click, what keys do you press, what do you see, etc.)>
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WinSCP 6.3.2

Error message:
List index out of bounds (0)

Rastreo de la pila:
(0020DE11) System::Classes::TStringList::GetObject
(0020DE11) System::Classes::TStringList::GetObject
(00B7F023) UnixExtractCommonPath
(00B76FC9) Queue::C4128_0
(00B7BCCC) TDeleteQueueItem::TDeleteQueueItem
(00019439) TCustomScpExplorerForm::DeleteFiles
(00012AEA) TCustomScpExplorerForm::ExecuteDeleteFileOperation
(00012B9E) TCustomScpExplorerForm::ExecuteFileOperation
(00012DD8) TCustomScpExplorerForm::ExecuteFileOperation
(00012F97) TCustomScpExplorerForm::ExecuteFileOperationCommand
(0004F1A4) TNonVisualDataModule::ExplorerActionsExecute
(002757F0) System::Actions::TContainedActionList::ExecuteAction

(00E21D6D) C6608_3
(00E23347) _ReThrowException
(0001968D) TCustomScpExplorerForm::DeleteFiles
(00012AEA) TCustomScpExplorerForm::ExecuteDeleteFileOperation
(00012B9E) TCustomScpExplorerForm::ExecuteFileOperation
(00012DD8) TCustomScpExplorerForm::ExecuteFileOperation
(00012F97) TCustomScpExplorerForm::ExecuteFileOperationCommand
(0004F1A4) TNonVisualDataModule::ExplorerActionsExecute
(002757F0) System::Actions::TContainedActionList::ExecuteAction

The problem happens rarely. I cannot reproduce it.