Codex Windows desktop app keeps the chat content area and message input field unnecessarily narrow

What issue are you seeing?

Problem

In the Codex Windows desktop app, the main chat content area remains narrow and centered even when the left sidebar and right panel are closed.

When I click an attached document in a conversation, the document opens in the right panel and can use a much larger, nearly full-screen area. However, the main chat area remains narrow and centered, leaving a large amount of unused horizontal space on both sides.

The message input field is also limited to a small area. When writing a long message, I have to scroll up and down inside the input field repeatedly because I cannot see the full message comfortably.

I checked Settings but could not find an option to:

• Use a wider or full-width chat layout
• Adjust the maximum width of the chat content
• Resize the message input field

What steps can reproduce the bug?

Steps to reproduce

1. Open the Codex desktop app on Windows.
2. Open a conversation.
3. Close the left sidebar and any right-side panel.
4. Maximize the application window on a wide monitor.
5. Observe that the conversation remains constrained to a narrow centered column.
6. Write a long multi-paragraph message in the composer.
7. Observe that the composer has a limited fixed height and requires internal scrolling to review the message.

What is the expected behavior?

Actual behavior

The main chat content stays in a narrow centered column.

• Closing the left and right panels does not expand the chat content area.
• Attached documents can open in the right panel and use much more of the available screen width, while the chat itself remains narrow.
• The message input field has a limited height and requires internal scrolling for long messages.

Expected behavior

Please add a display/layout setting for conversation width, such as:

• Full width
• Wide layout
• Adjustable maximum content width
• Compact / Standard / Wide layout modes**
  The setting should allow the chat transcript, tables, code blocks, logs, and structured output to use more of the available horizontal space after side panels are closed.
  Please also make the message composer vertically resizable:
• Users should be able to drag the top edge of the composer to increase or decrease its height.
• The composer should support a reasonable minimum and maximum height.
• The selected composer height should ideally persist for future conversations.
• This would let users review and edit long prompts without constantly scrolling inside a small text area.

Additional context

Zooming can make text larger, but it does not solve the underlying layout problem because the content column remains narrow and the composer height remains limited. A dedicated content-width setting and a resizable message composer would significantly improve readability and make better use of large desktop displays.

Expected behavior

• Add a setting to choose the chat content width, for example:
  • Compact
  • Standard
  • Wide
  • Full width
  • Adjustable maximum content width
• The chat area should expand to use more available space when side panels are closed.
• Make the message input field vertically resizable by dragging its top edge.
• Let users resize the input field within reasonable minimum and maximum heights.
• Ideally, remember the user’s chosen input-field height across conversations.

Additional information

No response

No files, tests, or entry points are named. Start by locating the Windows desktop conversation layout and message composer implementation, then trace how panel visibility and user settings are handled. Done means users can choose a wider chat layout and resize the composer within defined limits, with the selected height retained if supported.