Termux + SSH + Zellij: inline mode scrollback appears truncated / jumps to pre-Codex history

Checklist

• [x] I can reproduce this consistently
• [x] I am using latest stable Codex CLI (0.101.0)
• [x] I tested with --no-alt-screen and tui.alternate_screen = "never"

Environment

• Client device: Android (Termux)
• Access path: Termux -> ssh -> remote Linux server -> zellij -> codex
• Codex CLI: 0.101.0
• Zellij: 0.43.1
• TERM: xterm-256color
• Codex config:
• tui.alternate_screen = "never"
• tui.animations = false
• tui.show_tooltips = false
• Zellij config (relevant):
• default_mode = "normal"
• mouse_mode = true
• scroll_buffer_size = 1000000

Problem

In this specific chain (Termux + SSH + Zellij), Codex output appears to be truncated during interaction.
When scrolling up in zellij, I often cannot see the full Codex history; it quickly jumps to content from before launching Codex.

So in practice, Codex conversation history is not reliably scrollable in this environment.

Expected behavior

With --no-alt-screen / alternate_screen = "never", Codex output should remain in normal terminal scrollback and be fully scrollable via zellij scrollback.

Actual behavior

• Codex history looks partially missing/truncated while running.
• Upward scroll can jump to pre-Codex content instead of older Codex output.
• Increasing zellij scroll_buffer_size does not fix it.

Reproduction steps

1. On Android Termux, SSH into Linux server.
2. Start zellij (zellij -s remote).
3. Run Codex with inline mode (codex --no-alt-screen).
4. Use Codex for a while to generate enough output.
5. In zellij, enter scroll mode and scroll up.

What I already tried

• codex --no-alt-screen
• ~/.codex/config.toml with tui.alternate_screen = "never"
• tui.animations = false
• tui.show_tooltips = false
• zellij default_mode = "normal"
• zellij scroll_buffer_size = 1000000

None resolved the core issue.

Additional notes

I captured startup output with script and confirmed no alt-screen sequence (ESC[?1049h) in this case, but Codex still sends many cursor positioning / clear-line / clear-screen sequences (CSI H, CSI K, CSI J) for redraw.
This may be interacting badly with scrollback in Termux + ssh + zellij path.

Happy to provide more logs if there is a preferred debug format.