TUI reasoning shortcuts do not work in VS Code integrated terminal on macOS

[kgruiz]

What version of Codex CLI is running?

codex-cli 0.124.0

What subscription do you have?

Pro Lite

Which model were you using?

gpt-5.5

What platform is your computer?

Darwin 25.5.0 arm64 arm

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

VSCode

What issue are you seeing?

The new keyboard shortcuts to change reasoning that were added in #18866 work in Ghostty on macOS, but do not work in the VS Code integrated terminal, even when terminal.integrated.macOptionIsMeta set to true.

What steps can reproduce the bug?

1. Ensure terminal.integrated.macOptionIsMeta is set to true in VS Code's settings.
2. Run Codex in VS Code's integrated terminal.
3. Attempt to change reasoning level using ⌥ + , or ⌥ + ..
4. The reasoning level is not changed, nor or do any other characters appear typed into the composer area (unlike when terminal.integrated.macOptionIsMeta is false, where ≤ and ≥ appear).

What is the expected behavior?

When either ⌥ + , or ⌥ + . is pressed, the reasoning level should be changed.

Additional information

When cat is run in Ghostty and in the VS Code integrated terminal, it shows that the two are sending different sequences.

In the VS Code integrated terminal with "terminal.integrated.macOptionIsMeta": true, pressing ⌥ + , and ⌥ + . shows:

^[,^[.

In Ghostty, pressing the same keys shows:

^[[44;5u^[[46;5u