Web sidebar shows duplicate entries for same session after /rename (old title persists)

Description

The web sidebar at claude.ai/code shows two entries for a single session
after the session's title was changed via /rename. Both entries point to the
same session_* URL (i.e., the same underlying session) — only the displayed
title differs (old vs new).

Reproduction

1. Create a Claude Code session in VSCode extension with auto-assigned title,

e.g. 데이터 흐름도 작성 점검.

1. Rename the session to #06] 데이터 흐름도 작성 점검 via /rename (or a script

that appends #NN] prefix to customTitle in the local JSONL).

1. Open claude.ai/code sidebar.

Observed: two entries listed:

• 데이터 흐름도 작성 점검 (pre-rename title)
• #06] 데이터 흐름도 작성 점검 (post-rename title)

Both link to the same URL https://claude.ai/code/session_01YAjPafeCwYnC4smK4dRe8K.

Expected: single entry showing the current title only.

Workarounds tried (none resolved)

• Hard refresh (Ctrl+F5)
• Logout / login
• Waiting past the ~10 min inactivity timeout

Data safety concern

Users cannot safely "deduplicate" via the web UI because deleting one entry
appears to delete the underlying local JSONL file (both entries share the same
session). This leaves the user with a permanently duplicated sidebar.

Environment

• Claude Code v2.1.112 (VSCode extension + CLI)
• Platform: Windows 11 Pro 10.0.26100
• \remoteControlAtStartup: true\ (in \~/.claude.json\)
• Multiple sessions affected; ~5 duplicates observed across one project

Related observation

For one long-running local session (UUID \6ade7e14-...\), the sidebar shows
5 separate entries, each backed by a distinct \session_*\ web ID recorded
in the JSONL's \type:\"system\"\ entries (one per claude.exe spawn/resume). This
suggests the web UI lists every historical API session rather than
consolidating to the latest — a related but distinct issue.