[Regression] [Error] unhandlederror-command 'workbench.userDataSync.actions.turnOn' not found

[vs-code-engineering]

Error Message

unhandlederror-command 'workbench.userDataSync.actions.turnOn' not found

Stack Trace

    at w9e._tryExecuteCommand (./src/vs/workbench/services/commands/common/commandService.ts:95:25)
    at w9e.executeCommand (./src/vs/workbench/services/commands/common/commandService.ts:89:14)
    at async Kge.value (./src/vs/workbench/contrib/preferences/browser/settingsEditor2.ts:2168:0)

Raw Stack Trace (minified)

Error: command 'workbench.userDataSync.actions.turnOn' not found     at w9e._tryExecuteCommand (out/vs/sessions/sessions.desktop.main.js:1274:4829)     at w9e.executeCommand (out/vs/sessions/sessions.desktop.main.js:1274:4729)     at async Kge.value (out/vs/sessions/sessions.desktop.main.js:1357:78758)

Details

Property	Value
Bucket ID	8c69f4a8-e3ea-d241-a714-fac8e7f00348
Version	1.118.0-insider
Commit	f2b51f3f
Last Seen	Sat Apr 25 2026 21:31:58 GMT+0000 (Coordinated Universal Time)
Platforms	Mac, Windows
Product	Agents

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This issue was automatically created from the VS Code Errors Dashboard

[vs-code-engineering]

Regression Details

• Product: Agents
• Regression type: new
• Last release without this error: 1.115.0 (41dd792, stable)
• First release with this error: 1.118.0-insider (102df5b, Apr 22)
• Commit range: 41dd792b...102df5b5

Deminified Stack (top frames)

#	Source	Line
1	commandService.ts	95
2	commandService.ts	89
3	settingsEditor2.ts	2168

The error command 'workbench.userDataSync.actions.turnOn' not found is thrown when the settings editor tries to execute the workbench.userDataSync.actions.turnOn command, which no longer exists. The error was first detected in 1.118.0-insider (Apr 22) and is absent from 1.115.0 stable. It affects 14 users with 24 hits on the target build, appearing on Windows and Mac.

Note: The commit range is wide (1.115.0 stable → earliest 1.118.0-insider) because all available insider builds with data show this error. The error also appears with different bucket IDs in earlier insider builds (df2f6c35 on Apr 22, 14acda7f on Apr 24) due to minification drift.

Generated by errors-regression-scan · ● 4.6M · ◷

[vs-code-engineering]

🔍 Error Investigation

Summary

The Agents (sessions) product includes the Settings Editor UI, which shows a "Backup and Sync Settings" button when sync services are available. However, the userDataSync.contribution.js module — which registers the workbench.userDataSync.actions.turnOn command — is never imported in the sessions product entry points (sessions.common.main.ts / sessions.desktop.main.ts). When users open the Settings Editor and click the button, the command is not found and an unhandled error is thrown. This affects 14+ users on the current build and has been present across multiple 1.118.0-insider builds (112 total hits across 3 error buckets).

Culprit Commit

No single culprit commit was identified. This is an architectural gap in the Agents/sessions product: the sync services were included (enabling the UI), but the sync contribution that registers the commands was omitted. The error has been present since at least commit 102df5b5 (April 22), which is the earliest Insider build where the error appears.

Related context: PR #311704 by @jrieken intentionally removed several unused contributions from the sessions app but did not add or remove userDataSync contributions — the gap predates that cleanup.

Code Flow

sequenceDiagram
    participant User as User (Settings Editor)
    participant SE as settingsEditor2.ts
    participant SC as SyncControls
    participant CS as CommandService

    User->>SE: Opens Settings Editor
    SE->>SE: Check userDataSyncWorkbenchService.enabled<br/>&&  canToggleEnablement()
    Note over SE: ✅ Both true (sync services loaded<br/>in sessions.desktop.main.ts)
    SE->>SC: Create SyncControls (line 784)
    SC->>SC: update() → show "Backup and Sync" button
    User->>SC: Clicks button (line 2167)
    SC->>CS: executeCommand('workbench.userDataSync.actions.turnOn')
    CS->>CS: _tryExecuteCommand (line 92)
    Note over CS: ⚠️ CommandsRegistry.getCommand(id)<br/>returns undefined
    Note over CS: 💥 Error: command<br/>'workbench.userDataSync.actions.turnOn'<br/>not found

Loading

Affected Files

File	Role
src/vs/sessions/sessions.desktop.main.ts	Root cause — imports sync services (lines 70-71, 86) but not userDataSync.contribution.js
src/vs/sessions/sessions.common.main.ts	Root cause — also missing the contribution import (compare workbench.common.main.ts:401)
src/vs/workbench/contrib/preferences/browser/settingsEditor2.ts	Crash site — creates SyncControls at line 783, button click executes missing command at line 2168
src/vs/workbench/services/commands/common/commandService.ts	Error origin — throws at line 95 when command not in registry
src/vs/workbench/contrib/userDataSync/browser/userDataSync.contribution.ts	Missing module — registers UserDataSyncWorkbenchContribution which registers the turnOn command

Repro Steps

1. Open VS Code Insiders with the Agents product (sessions desktop)
2. Open the Settings Editor (Ctrl+, / Cmd+,)
3. Ensure Settings Sync is not currently enabled
4. Observe the "Backup and Sync Settings" button appears in the header
5. Click the "Backup and Sync Settings" button
6. Error is thrown: command 'workbench.userDataSync.actions.turnOn' not found

Fix Proposal

Two approaches depending on whether Settings Sync should be supported in the Agents product:

Option A — Enable sync in Agents (if intended):
Add the missing contribution imports to the sessions entry points:

• src/vs/sessions/sessions.common.main.ts → add import '../workbench/contrib/userDataSync/browser/userDataSync.contribution.js'
• src/vs/sessions/sessions.desktop.main.ts → add import '../workbench/contrib/userDataSync/electron-browser/userDataSync.contribution.js'

Option B — Disable sync UI in Agents (if sync is not intended):
Guard the SyncControls creation in settingsEditor2.ts → createHeader() (line 783). Either:

• Check that the command exists before showing the button (e.g., CommandsRegistry.getCommand('workbench.userDataSync.actions.turnOn'))
• Or remove the sync services from the sessions entry points so userDataSyncWorkbenchService.enabled returns false

Fix location: src/vs/sessions/sessions.common.main.ts and/or src/vs/sessions/sessions.desktop.main.ts
Approach: Add the missing userDataSync.contribution.js imports (Option A) or make the settings editor defensive about the missing command (Option B)

Recommended Owner

@sandy081 — Area owner for Settings Sync, and actively works on the sessions/agents product infrastructure

Generated by errors-investigate · ● 12.9M · ◷

[vs-code-engineering]

Related Error Buckets

These additional error buckets are tracked by this issue (v1.119.0-insider):

Bucket	Error Message	Version
d8b1d2c9	command 'workbench.userDataSync.actions.turnOn' not found	1.119.0-insider

Stack: commandService.ts:95 → commandService.ts:89 → settingsEditor2.ts:2168

Trend: Single version only (1.119.0-insider), 15 users, 25 hits.

Generated by errors-triage · ● 31.4M · ◷

[vs-code-engineering]

Related Error Buckets

These additional error buckets are tracked by this issue (v1.118.0-insider, Agents product):

Bucket	Error Message	Version
14acda7f	command 'workbench.userDataSync.actions.turnOn' not found	1.118.0-insider

Deminified stack:

• commandService.ts:95 → _tryExecuteCommand
• commandService.ts:82 → raceCancellablePromises

Generated by errors-triage · ● 49.6M · ◷