[BUG] CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 disables TUI scrollback in v2.1.119 (terminal can't scroll up to view earlier turns)

Preflight Checklist

• [x] Searched existing issues (related: #52673, #52251, #52139, #38932 — all Agent-Teams+TUI in 2.1.119, but none specifically about scrollback)
• [x] Single bug report
• [x] Latest version (2.1.119)

What's Wrong?

Setting CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 before launching claude in v2.1.119 silently disables terminal scrollback. The user can't scroll up to see earlier turns in the conversation. Mouse wheel and PageUp/PageDown produce no movement past the visible viewport.

The exact same terminal, the exact same launch command WITHOUT the env var, produces a fully-scrollable session.

Repro

Same machine, same terminal (tested in Linux screen wrapper + VS Code integrated terminal — identical behavior in both):

Scroll WORKS:
\\\bash
cd ~/project && \\
claude --resume --permission-mode auto --channels \"plugin:discord@claude-plugins-official\"
\\\

Scroll BROKEN:
\\\bash
cd ~/project && \\
export CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1 && \\
claude --resume --permission-mode auto --channels \"plugin:discord@claude-plugins-official\"
\\\

Single-variable differential. Same flags, same session-resume, same terminal. Only the env var differs.

What Should Happen?

Setting the experimental teams flag should not change scrollback behavior. User should be able to scroll up through prior turns in either mode.

Settings.json

\tui: default\ is set in \~/.claude/settings.json\. The cycle-22 doc notes this was a workaround for the 2.1.89+ alt-screen-buffer issue (#42670). Without the teams flag, the workaround is effective. With the teams flag, the workaround appears to be bypassed/overridden.

Environment

• Claude Code version: 2.1.119
• Platform: Linux Debian 12 (Raspberry Pi 5, aarch64) running CC server, accessed via SSH
• Terminal: GNU screen 4.09 wrapper, also reproduced in VS Code remote SSH terminal
• Settings: \tui: default\ (the post-2.1.89 scrollback workaround)
• Plugins enabled: discord plugin via channels flag

Why This Matters

Agent Teams is the workflow for multi-agent dispatch. Losing scrollback in team mode forces a choice: either you have parallel agent dispatch but no conversation history, or you have history but no team. Both are needed in normal workflow.

The differential is so clean (one env var) that it suggests the teams flag toggles a render mode that doesn't go through the same alt-screen-handling code path that \tui: default\ configures.

Likely related — same release / same area: #52673 (Ink renderer source leaks in Agent Teams + 2.1.119), #52251 (subagent SendMessage in Agent Teams), #52139 (Ink renderer crashes in spawned teammates).

Workaround (current)

Strip \CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1\ from launch script. Keeps scrollback at the cost of losing the teams MCP server (TeamCreate / TeamDelete / SendMessage). Use one-off \Agent()\ dispatches as fallback.