[Error] unhandlederror-Cannot read properties of undefined (reading 'panel')

[vs-code-engineering]

Error Message

unhandlederror-Cannot read properties of undefined (reading 'panel')

Stack Trace

    at C6.setCurrentLanguageModel (./src/vs/workbench/contrib/chat/browser/widget/input/chatInputPart.ts:1219:0)
    at C6._syncFromModel (./src/vs/workbench/contrib/chat/browser/widget/input/chatInputPart.ts:1136:0)
    at yB._runFn (./src/vs/workbench/contrib/chat/browser/widget/input/chatInputPart.ts:1071:0)
    at yB.run (./src/vs/base/common/observableInternal/reactions/autorunImpl.ts:110:10)
    at new yB (./src/vs/base/common/observableInternal/reactions/autorunImpl.ts:58:7)
    at ve (./src/vs/base/common/observableInternal/reactions/autorun.ts:20:8)
    at autorun (./src/vs/workbench/contrib/chat/browser/widget/input/chatInputPart.ts:1065:0)
    at my.setModel (./src/vs/workbench/contrib/chat/browser/widget/chatWidget.ts:2080:0)
    at U.showModel (./src/vs/workbench/contrib/chat/browser/widgetHosts/viewPane/chatViewPane.ts:762:0)
    at async (./src/vs/workbench/contrib/chat/browser/widgetHosts/viewPane/chatViewPane.ts:872:0)
    at async r (./src/vs/workbench/services/progress/browser/progressService.ts:54:0)

Raw Stack Trace (minified)

TypeError: Cannot read properties of undefined (reading 'panel')     at C6.setCurrentLanguageModel (out/vs/workbench/workbench.desktop.main.js:2747:159248)     at C6._syncFromModel (out/vs/workbench/workbench.desktop.main.js:2747:157756)     at yB._runFn (out/vs/workbench/workbench.desktop.main.js:2747:156641)     at yB._run (out/vs/workbench/workbench.desktop.main.js:407:6694)     at new yB (out/vs/workbench/workbench.desktop.main.js:407:5832)     at ve (out/vs/workbench/workbench.desktop.main.js:407:8931)     at C6.setInputModel (out/vs/workbench/workbench.desktop.main.js:2747:156538)     at my.setModel (out/vs/workbench/workbench.desktop.main.js:2930:67556)     at U_.showModel (out/vs/workbench/workbench.desktop.main.js:3300:45444)     at async out/vs/workbench/workbench.desktop.main.js:3300:47210     at async r (out/vs/workbench/workbench.desktop.main.js:1767:15533)

Details

Property	Value
Bucket ID	c5714e8c-c14d-da50-88e3-43720e1a8275
Version	1.121.0
Commit	f6cfa2ea
Last Seen	Wed May 20 2026 23:49:53 GMT+0000 (Coordinated Universal Time)
Platforms	Mac, Windows, Linux
Product	VSCode

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This issue was automatically created from the VS Code Errors Dashboard

[vs-code-engineering]

Stable Release Anomaly Details

Property	Value
Anomaly type	new
Previous stable	1.120.0
Current stable	1.121.0
Last release without this error	1.120.0
First release with this error	1.121.0-insider (c305abcf)
Commit range	compare
Users (current stable)	253
Platforms	Mac, Windows, Linux

Deminified Stack Summary

• chatInputPart.ts:1219 → setCurrentLanguageModel
• chatInputPart.ts:1136 → _syncFromModel
• chatInputPart.ts:1071 → autorun
• chatWidget.ts:2080 → setModel
• chatViewPane.ts:762 → showModel

Generated by errors-stable-scan · ● 8.3M · ◷