Composer 2 (Fast mode) produces garbled text / encoding issues

Support Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When using Composer 2 in Fast mode, the generated text sometimes becomes corrupted.
Parts of the output contain garbled characters (e.g., οΏ½), making the content hard to read.

Steps to Reproduce

  1. Enable Composer 2 Fast mode
  2. Ask a normal question
  3. Check the output

Expected Behavior

Text should be generated in clean, readable UTF-8 without any corruption.

Screenshots / Screen Recordings

스크란샷 2026-04-13 α„‹α…©α„Œα…₯ᆫ 9.49.53.png
스크란샷 2026-04-13 α„‹α…©α„Œα…₯ᆫ 9.49.53.png1566Γ—910 109 KB

Operating System

MacOS

Version Information

Version: 3.0.13
VSCode Version: 1.105.1
Commit: 48a15759f53cd5fc9b5c20936ad7d79847d914b0
Date: 2026-04-07T03:05:17.114Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Darwin arm64 25.4.0

For AI issues: which model did you use?

Composer 2 Fast

For AI issues: add Request ID with privacy disabled

e14e01c1-54a7-40c4-9066-805173bd3270

Does this stop you from using Cursor

No - Cursor works, but with this issue

3

I just updated Cursor and same issue happens with latest version

Version: 3.0.16
VSCode Version: 1.105.1
Commit: 475871d112608994deb2e3065dfb7c6b0baa0c50
Date: 2026-04-09T05:33:51.767Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Darwin arm64 25.4.0

6

Hey, this is a known issue with Composer 2 and Composer 2 Fast. It affects all CJK languages like Korean, Japanese, Thai, and more. The team is aware, and the Request ID has been accepted.

For now, the workaround is to use GPT-5.4 or Gemini 3.1 Pro for tasks with Korean text. These models handle UTF-8 correctly.

Related reports are collected here: [BUG]Korean characters broken (encoding issue) in Composer/Agent

There’s no ETA for a fix yet, but every report helps with prioritization. I’ll update the thread when I have more info.