Large chats in VSCode extremely slow to load

What version of the IDE extension are you using?

26.422.62136

What subscription do you have?

Pro

Which IDE are you using?

VS Code

What platform is your computer?

Darwin 25.4.0 arm64 arm

What issue are you seeing?

When I select a long-running chat, nothing appears in the Codex sidebar. Sometimes I can get the chat to appear if I click around to another chat and reload it, but not all the time. A loading bar with a percentage or some indication its loading would be very helpful. Otherwise I dont think its doing anything and start clicking around.

What steps can reproduce the bug?

1. Create a long-running chat in the codex extension
2. Close VS Code
3. Open VS Code
4. Attempt to load the chat

<img width="1402" height="1042" alt="Image" src="https://github.com/user-attachments/assets/53d38f3d-6a93-4580-a218-79173292abf5" />

What is the expected behavior?

The expected behavior is the chat loads(at least partially) immediately.

Additional information

_No response_