Thanks for your report.

Can you send me an email, so I can send you back a debug version of WinSCP to track the problem? Please include a link back to this topic in your email. Also note in this topic that you have sent the email. Thanks.

I work on my PC via default Windows RDP, and after I reconnect to remote after a while (e.g. at next day), my WinSCP window (GUI) doesn't respond, as if it frozen while I was disconnected or at the moment of connecting to RDP. But I cannot reproduce the problem now, it does not appear every time. The WinSCP window cannot be opened (maximized, it is hidden), and updates from editor are not sent to connected sites. At the same time, I can open another window in parallel and it will work, but some things from the frozen window are not saved (e.g, opened remote folder and site bookmarks).

Steps that lead to the problem:
Run WinSCP on the remote PC, connect to some sites (up to 4) via SSH/SFTP, open some files to edit in VS Code (up to 10 files), work with files, save changes, disconnect from RDP (remote PC and WinSCP continue to work always), turn off local computer. Then turn on local PC on the next day, connect to remote PC via RDP, try to open WinSCP - it doesn't open.

Environment:
WinSCP v5.19 (Build 11512)
Windows 10 Enterprise v21H1 (Build 19043.1052)
Connecting type - SFTP, SSH.
Default editor - VS Code.