Duplicate via local temporary copy lose permissions

When i use "Duplicate" and "Duplicate via local temporary copy" it seems that the permissions (RWX) get lost on the duplicate files. Should it really be like this?

WinSCP 5.17.5

Well, that's the way it is implemented currently.

This issue has been added to the tracker:
https://winscp.net/tracker/1867
You can vote for it there.