OSC52 clipboard escape sequences not working in Remote SSH terminal

Problem

OSC52 escape sequences for clipboard operations work in VS Code's local integrated terminal but are silently ignored when connected via Remote SSH.

Environment

• VS Code version: Latest (Feb 2026)
• Remote - SSH extension: Latest
• Local OS: macOS
• Remote OS: Ubuntu (headless server, no X11/DISPLAY)
• Terminal: VS Code integrated terminal

Steps to Reproduce

1. Connect to a remote server via VS Code Remote SSH
2. Open the integrated terminal
3. Run: printf "\033]52;c;$(printf "%s" "test clipboard" | base64)\007"
4. Try to paste (Cmd+V on Mac) in any application

Expected: "test clipboard" should be in system clipboard
Actual: Nothing is copied to clipboard

Evidence That Local Terminal Works

The same OSC52 command works perfectly in:

• VS Code's local integrated terminal
• iTerm2 with direct SSH connection
• Any terminal that supports OSC52

Related Issues

• xterm.js #3260 - OSC52 support added via PR #4220 (April 2024)
• VS Code #193508 - OSC52 support added to VS Code terminal (June 2024)
• GitHub Community #153471 - Same issue reported for Codespaces
• vscode-remote-release #5905 - Related clipboard feature request
• vscode-remote-release #8049 - tmux clipboard issue (duplicate)

Technical Analysis

OSC52 works by having the local terminal emulator intercept escape sequences and write to the system clipboard. Over SSH, these sequences should pass through transparently and be handled by the local VS Code terminal.

The issue appears to be that VS Code Remote SSH's terminal forwarding either:

1. Strips OSC52 sequences before they reach the local terminal emulator
2. The xterm.js clipboard addon isn't loaded/active in Remote SSH context
3. There's a security policy blocking clipboard access in remote terminal sessions

Impact

This breaks clipboard functionality for:

• CLI tools that use OSC52 (opencode, claude-code, neovim with OSC52 plugin, etc.)
• tmux copy-paste workflows
• Any remote development workflow requiring programmatic clipboard access

Workaround

Currently, users must either:

• Use mouse selection + Cmd+C (defeats the purpose of CLI tools)
• Use a separate terminal app (iTerm2) with direct SSH instead of VS Code Remote SSH

Request

Please ensure OSC52 escape sequences are properly forwarded and handled in Remote SSH terminal sessions, matching the behavior of local integrated terminals.

Reproduce the OSC52 command in a VS Code Remote SSH integrated terminal and compare it with the local terminal and direct iTerm2 SSH behavior. Read the related xterm.js #3260, VS Code #193508, and remote-release #5905 and #8049 discussions before tracing terminal forwarding. Done means OSC52 clipboard writes work remotely without breaking existing local behavior.