Broken terminal sequences

[postwait]

"OpenSSH for Windows" version
8.1.0.1

Server OperatingSystem
Windows 10 Pro

Client OperatingSystem
Linux (CentOS 7, Ubuntu 16/18/20.04)

What is failing
There is a terminal emulation issue with line-shift scrolling. I believe this is the openssh server or windows console incorrectly intercepting terminal control sequences.
From a Linux client (could be in WSL on the same box) to Windows server running WSL2:

ssh -t WindowsBox wsl
vi multipagefile.txt
<downarrow / j many times such that the document must line-scroll>

I've tried with both cmd.exe and Powershell as my default shell for windows.
I've also tried a variety of terminal settings TERM=(xterm|xterm-color256|vt102|vt100)

Expected output
Expected output that the document shifts (all lines)

Actual output
Only the top and bottom line of the document are re-rendered leaving the core contents not-redrawn.

[bagajjal]

@postwait - I wonder how you got v8.1.0.1. Are you internal to microsoft (or) part of internal ring to get newer version of windows (which is not yet ready for public)?

What vi application did you choose to install on windows?

[postwait]

I'm on insider fast ring but nothing else special.

I am not using vi on Windows... notice I'm sshing from Linux to Windows and then running wsl to hop into a Linux container on the Windows machine... So:

[Linux] - ssh -> [Windows] - wsl -> [Linux] vi

[bagajjal]

@postwait - I tried the same scenario. couldn't repro the issue.
From Ubuntu 20.04, I connected to windows machine (ssh.exe -t user@windows_ip wsl) to execute wsl. Then vi some file. I tried down, up, left, right arrow keys and h, j, k, l keys in non-insert mode.. They all worked.. I can see lines scrolling..

Did I get the scenario right?

[postwait]

That's the scenario... The file last to be more than one page so that the document scrolls up a line when you j past the bottom-most line in the editor. Once the screen is all messed up, if I hit CTRL-l it will repaint and look correct again.

[bagajjal]

@postwait - The document I tried is more than a page. It scrolls and renders properly when the cursor is at the end of page and renders the data correctly. I am using Microsoft Windows [Version 10.0.19041.329]. Please provide the output of cmd on a cmd.exe / powershell.exe. It looks like this,

OpenSSH uses console APIs to interpret the VTSeq and render the data correctly. I would like to repro first before involving the console team.

[postwait]

PS C:\Users\jesus> cmd
Microsoft Windows [Version 10.0.19645.1]
(c) 2020 Microsoft Corporation. All rights reserved.

I'll try to do a quick screen grab

[postwait]

terminal issue video

I start on the a WSL2 container.. ssh into the host containing it, then invoke wsl to get back into the same container to run the same vi command. At the very end, I hit ctrl-l to refresh the screen

[DHowett]

If you're on a version of windows between 19042 and 20000, there was a brief regression in the console APIs that OpenSSH uses to run applications on Windows. 😄

[bagajjal]

@DHowett - Is there a workaround? Does "Windows terminal" downloaded from store comes with latest and greatest supported conhost?