Prompt text box becomes extremely laggy when chat displays any rich UI elements

What version of the IDE extension are you using?

0.4.76

What subscription do you have?

Plus

Which IDE are you using?

VS Code

What platform is your computer?

Windows 11 25H2

What issue are you seeing?

Whenever there's anything else than plain text displayed in the codex chat panel, such as diff widgets or list of changed files with undo/review buttons, the prompt text box typing becomes extremely laggy and unresponsible, sometimes having up to several hundred millisecond input latency. Merely scrolling the UI elements out of the view to a part of the chat that has plain text fixes the lag.

What steps can reproduce the bug?

1. Open Codex Chat in a VSCode sidebar
2. Order agent to perform extensive changes across multiple files, which will result in diff and review widgets to be displayed in the chat log.
3. Hold down any key in the text prompt box, and watch the text appear with significant delay at extremely low framerate.
4. Scroll the chat log into a part of the chat where only plain markdown text is displayed
5. Hold down any key in the text prompt box, and watch the text appear immediately and smoothly

What is the expected behavior?

Widgets displayed in the chat log have no impact on the performance of the prompt text box.

Additional information

_No response_