List index out of bounds (0) - UnixExtractCommonPath

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WinSCP 6.3.5

Error message:
List index out of bounds (0)

Stack trace:
(0020DDD1) System::Classes::TStringList::GetObject
(0020DDD1) System::Classes::TStringList::GetObject
(00B815B7) UnixExtractCommonPath
(00B7955D) Queue::C4132_0
(00B7E260) TDeleteQueueItem::TDeleteQueueItem
(00019439) TCustomScpExplorerForm::DeleteFiles
(00012AEA) TCustomScpExplorerForm::ExecuteDeleteFileOperation
(00012B9E) TCustomScpExplorerForm::ExecuteFileOperation
(00012DD8) TCustomScpExplorerForm::ExecuteFileOperation
(00012F97) TCustomScpExplorerForm::ExecuteFileOperationCommand
(0004F0F6) TNonVisualDataModule::ExplorerActionsExecute
(002757CC) System::Actions::TContainedActionList::ExecuteAction
(003595AD) Vcl::Actnlist::TCustomAction::Execute
(00226F2C) System::Classes::_18201
(00032161) USER32.dll
(00022F51) USER32.dll
(00021810) USER32.dll
(0002135B) USER32.dll.DispatchMessageW

(00E24BDD) C6612_0
(00E261B7) _ReThrowException
(0001968D) TCustomScpExplorerForm::DeleteFiles
(00012AEA) TCustomScpExplorerForm::ExecuteDeleteFileOperation
(00012B9E) TCustomScpExplorerForm::ExecuteFileOperation
(00012DD8) TCustomScpExplorerForm::ExecuteFileOperation
(00012F97) TCustomScpExplorerForm::ExecuteFileOperationCommand
(0004F0F6) TNonVisualDataModule::ExplorerActionsExecute
(002757CC) System::Actions::TContainedActionList::ExecuteAction
(003595AD) Vcl::Actnlist::TCustomAction::Execute
(00226F2C) System::Classes::_18201
(00032161) USER32.dll
(00022F51) USER32.dll
(00021810) USER32.dll
(0002135B) USER32.dll.DispatchMessageW

The problem happens rarely. I cannot reproduce it.