Codex TUI input/prompt contrast is too low over SSH on Linux EC2 devbox

Codex version

codex-cli 0.115.0

Environment

• Host: macOS
• Terminal: iTerm2
• Connection: SSH into Linux EC2 devbox
• Remote shell: zsh
• Remote terminal env:
• TERM=xterm-256color
• COLORTERM unset
• TERM_PROGRAM unset

Problem

When I run Codex on this remote EC2 box over SSH, my typed prompt/input is not visually distinct from Codex output. The prompt/input area appears to have little or no contrast difference, so it’s hard to tell my input apart from assistant text.

Expected behavior

My input/prompt should be clearly distinguishable from Codex output, with a readable, high-contrast style.

Actual behavior

Input/output contrast is too low or effectively absent in this environment.

What’s interesting

• Codex works fine on the host Mac directly in iTerm2.
• Codex also works fine when I SSH into other machines.
• This appears specific to this Linux EC2 devbox environment.

Things I tried

• Changing theme inside Codex with /theme
• Restarting Codex after theme changes
• Exporting:
• COLORTERM=truecolor
• COLORFGBG=15;0
• Verifying shell prompt theming separately (Powerlevel10k works, but does not affect Codex TUI behavior)

Repro

1. From macOS/iTerm2, SSH into the Linux EC2 devbox.
2. Run codex.
3. Type a prompt in the Codex TUI.
4. Observe that the typed input is not clearly visually separated from Codex output.

Notes

This looks like a terminal/theme detection issue in the Codex TUI rather than a shell prompt/theme issue.