Add in-thread navigation / table of contents for long sessions in Desktop App

What variant of Codex are you using?

App (Desktop)

What feature would you like to see?

Problem

In long coding sessions, conversations can easily grow to hundreds or thousands of messages.

Currently, navigating older parts of a session in the Desktop App mainly requires manually scrolling upward through the chat history. This becomes inefficient when trying to revisit:

• earlier architecture decisions
• previous code suggestions
• debugging steps
• summarized plans or checkpoints

While session history/search helps locate conversations, there is no convenient way to navigate within a long conversation.

Proposed feature

Add in-thread navigation features for long sessions, such as:

• Table of contents / outline panel

• Automatically generate a navigable outline from user prompts, assistant summaries, or section markers.

• Jump to message / search within current thread

• Search only inside the active session and jump directly to matching messages.

• Collapsible sections

• Allow collapsing older sections of a conversation to reduce visual clutter.

• Manual bookmarks / anchors

• Let users bookmark important messages or checkpoints.

Example use cases

During long coding workflows, users often need to quickly return to:

• initial requirements
• earlier API designs
• bug root cause discussions
• implementation summaries

A navigation panel similar to:

• VS Code Outline
• Notion block navigation
• Slack jump/search

would significantly improve usability for long-running sessions.

Why this matters

Codex is especially useful for large and iterative engineering tasks, which naturally create very long conversations.

As sessions grow longer, lack of in-thread navigation becomes a UX bottleneck and makes context revisiting unnecessarily slow.

Additional information

Related pain points seem connected to existing issues around session history/indexing/sidebar consistency, but this request is specifically about improving navigation inside a single long session.