LLM output is not displayed properly when running codex cli in alacritty + tmux

What version of Codex CLI is running?

codex-cli 0.104.0

What subscription do you have?

Plus

Which model were you using?

gpt-5.3-codex

What platform is your computer?

Macos

What terminal emulator and version are you using (if applicable)?

Alacritty + tmux

What issue are you seeing?

If I maximize the tmux pane while codex is generating output, the output gets messed up and some text is not visible in the terminal history anymore.

What steps can reproduce the bug?

Type this in codex cli with alacritty + tmux:

output numbers from 1 to 200 slowly. I'm trying to debug codex cli

While it's generating output, maximize and minimize the pane repeatedly. After that, enable copy mode (scroll mode) and scroll up. You'll see something like this in the scrollback buffer:

↳ Interacted with background terminal · for i in {1..200}; do echo $i; sleep 0.15; done
  └ (waited)

• 10
  11
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  59

↳ Interacted with background terminal · for i in {1..200}; do echo $i; sleep 0.15; done
  └ (waited)

• 60
  61
  62
  63
  64
  65
  66
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  125
  126
  127
  128
  129
  130
  131
  132
  133
  134


↳ Interacted with background terminal · for i in {1..200}; do echo $i; sleep 0.15; done
  └ (waited)

• Ran for i in {1..200}; do echo $i; sleep 0.15; done
  └ 2
    3
    … +195 lines
    199
    200

────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

• 135
  136
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  191

↳ Interacted with background terminal
  └ (waited)

• 192
  193
  194
  195
  196
  197
  198
  199
  200

• Finished streaming 1 to 200 slowly.

Notice that some lines are missing.

What is the expected behavior?

Everything that the LLM outputs should be visible in the terminal. This bug messes up LLM output and makes it unreadable.

Additional information

_No response_