Strange character sequences (ANSI escape sequences?) leaking into shell prompt when starting/attaching Tmux

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Prerequisites

• [X] Write a descriptive title.
• [X] Make sure you are able to repro it on the latest version
• [X] Search the existing issues.

Steps to reproduce

Connect to a Linux/Unix host via ssh and attach to a tmux session. Strangely the results seem to differ based on the target OS, e.g.:

• On an EoL CentOS 7 and a Fedora Linux 40 system I reliably get 61;6;7;21;22;23;24;28;32;42c (basically every time)
• On a Debian 12 host I get 0;10;1c but only on every third/fourth attempt or so

Expected behavior

I can attach to my Tmux session and it looks exactly as I left it. This usually means that the last line of the active Tmux window/pane contains a empty shell prompt like this:

[michael@groot ~]$

Actual behavior

I get some additional random characters ("garbage") behind the prompt, e.g.:

[michael@groot ~]$ 61;6;7;21;22;23;24;28;32;42c

Error details

No response

Environment data

I am using the Windows Terminal and it doesn't matter if I uses the "Windows PowerShell", "Command Prompt", or "Git Bash". When I use "Git Bash" via "Windows Terminal" everything works as expected with /usr/bin/ssh (OpenSSH_9.7p1, OpenSSL 3.2.1 30 Jan 2024) but not with /c/Program\ Files/OpenSSH/ssh (OpenSSH_for_Windows_9.5p1, LibreSSL 3.8.2) which is why I came to the conclusion that this seems to be a OpenSSH for Windows bug. The second indication that this seems to be an OpenSSH for Windows bug is that I didn't get those unexpected character sequence with SSH_TERM_CONHOST_PARSER=0 (but that also makes the rendering much much slower and I get significant visual glitches like a green background color (probably due to the status line background color from tmux)).

Anyway, here is the desired output but I don't expect it to be relevant in this case:

Name                           Value
----                           -----
PSVersion                      5.1.19041.4894
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.19041.4894
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

Version

OpenSSH_for_Windows_9.5p1, LibreSSL 3.8.2

Visuals

No response