Error transferring file '/PDRS/app/model/pdrs/attributes.php' - TFileOperationProgressType::SetTransferSize

I accidentally quickly pressed enter twice when opening a file, and this error popped up.
Might be worth noting I'm using external editor notepad++ and the transfer mode is set to text.

It looks like I'm able to reproduce it, by selecting file and quickly tapping enter twice to open it

WinSCP 5.7.7

Error message:
Error transferring file '/PDRS/app/model/pdrs/attributes.php'.

Invalid access to memory.

Stack trace:
(00649EA5) TFileOperationProgressType::SetTransferSize
(007E08AA) C4799_0
(007E2912) ____ExceptionHandler
(007DF88C) __ExceptionHandler
(00062496) ntdll.dll
(0000F13E) ntdll.dll.KiUserExceptionDispatcher
(0065221F) TFTPFileSystem::DoFileTransferProgress
(0065232B) TFTPFileSystem::FileTransferProgress
(0065FF3E) TFTPFileSystem::HandleTransferStatus
(0064C96F) TFileZillaImpl::HandleTransferStatus
(004D53E1) TFileZillaIntf::HandleMessage
(0065A6AC) TFTPFileSystem::ProcessMessage
(0065A93B) TFTPFileSystem::DoWaitForReply
(0065AA27) TFTPFileSystem::WaitForReply
(0065AA80) TFTPFileSystem::WaitForCommandReply
(00653DBE) TFTPFileSystem::Sink
(006529F0) TFTPFileSystem::SinkRobust
(006527EF) TFTPFileSystem::CopyToLocal
(00724619) TTerminal::CopyToLocal
(0000F999) TCustomScpExplorerForm::TemporarilyDownloadFiles
(0001059E) TCustomScpExplorerForm::ExecuteFile
(00010B7E) TCustomScpExplorerForm::ExecuteFile
(00016119) TCustomScpExplorerForm::DoDirViewExecFile
(00015FEE) TCustomScpExplorerForm::DirViewExecFile

(007E0F15) C4799_0
(007E24EF) _ReThrowException
(0065A9A8) TFTPFileSystem::DoWaitForReply
(0065AA27) TFTPFileSystem::WaitForReply
(0065AA80) TFTPFileSystem::WaitForCommandReply
(00653DBE) TFTPFileSystem::Sink
(006529F0) TFTPFileSystem::SinkRobust
(006527EF) TFTPFileSystem::CopyToLocal
(00724619) TTerminal::CopyToLocal
(0000F999) TCustomScpExplorerForm:%

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.

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.

This is most probably just another manifestation of this bug:
https://winscp.net/tracker/1369