[BUG] [Web UI] Response renders appended to last output instead of below user input; spinner persists incorrectly

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Bug Description

In Claude Code Cloud (CCC) web UI, two rendering issues:

1. Response misplacement: Assistant responses appear appended to the

bottom of the previous assistant output, instead of rendering below
the user's latest input. This makes it easy to miss new responses.

1. Persistent spinner: The loading indicator (spinning animation +

status words) continues to display even after the assistant has
finished generating, making it unclear whether work is still in progress.

Steps to Reproduce

1. Open Claude Code via web UI (cloud session)
2. Send a message and receive a response
3. Send a follow-up message
4. Observe: the new response attaches to the end of the previous response

block rather than appearing after the new user input

Expected Behavior

• New responses should appear below the corresponding user input
• Spinner should stop when generation is complete

Environment

• Platform: Claude Code Cloud (web UI)
• Date observed: 2026-03-07

<img width="771" height="1250" alt="Image" src="https://github.com/user-attachments/assets/ba65a2c0-f82f-4f29-9af9-3dc6ee9ed645" />

What Should Happen?

When a user sends a new message in the Claude Code Web UI:

1. The user's input should appear in the conversation flow
2. The assistant's response should render directly below that user input
3. The loading spinner should stop as soon as the response generation is complete

Currently:

• The response is appended to the bottom of the previous assistant output,

not below the latest user message — making it easy to miss new responses

• The spinner continues to animate after generation has finished,

giving the false impression that work is still in progress

Error Messages/Logs

Steps to Reproduce

1. Open Claude Code on the web (claude.ai/code)
2. Send a message and wait for a full response
3. Send a follow-up message
4. Observe the response placement:

• Actual: new response appears attached to the tail of the

previous assistant block (need to scroll up past your own input
to find it)

• Expected: new response appears below your latest input

1. Observe the spinner:

• Actual: spinning animation + rotating verb labels persist

after the response has fully rendered

• Expected: spinner stops when generation completes

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.42

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_