Cannot Sign In to Extension: getting The request body must contain the following parameter: 'client_assertion' or 'client_secret'.

[SapiensID]

When signing into Fabric, first I get a notification that says "the extension 'Microsoft Fabric' wants to sign in using Microsoft'. I click "allow" then I get another window from "Sign in to Code Helper (Plugin) with single sign-on" that contains my two work accounts. This seems to be a helper from "Company Portal" (my mac is work provisioned through Intune).

After selecting one of the accounts, I get:

Error getting session for vscode-fabric-identity: NativeAuthError: ApiContractViolation: AADSTS7000218 
Description: Error Domain=MSAIMSIDOAuthErrorDomain Code=-51411 "(null)" UserInfo={MSAIMSIDErrorDescriptionKey=AADSTS7000218: The request body must contain the following parameter: 'client_assertion' or 'client_secret'. 
Trace ID: 538c4b5a-0018-43d6-b085-a4fedd43cb00 
Correlation ID: 57c3528a-bb54-4526-9a39-41e4ff751ae4 
Timestamp: 2025-10-15 14:09:40Z, 
MSAIMSIDBrokerVersionKey=5.2510.0, 
MSAIMSIDOAuthErrorKey=invalid_client, 
MSAIMSIDCorrelationIdKey=57C3528A-BB54-4526-9A39-41E4FF751AE4}, 
Domain: MSAIMSIDOAuthErrorDomain.
Error was thrown in sourceArea: Broker (Error Code: -51411, Tag: 4lv13)

I can sign in without any problem to the extension Fabric Data Engineering.

When I look in vscode settings "Microsoft-Authentication: Implementation" I have the option "msal" selected.

fabric.vscode-fabric --v: 0.26.4
synapsevscode.synapse --v: 1.15.0
Version: 1.105.0 (Universal)
Commit: 03c265b1adee71ac88f833e065f7bb956b60550a
Date: 2025-10-08T14:09:35.891Z (1 wk ago)
Electron: 37.6.0
ElectronBuildId: 12502201
Chromium: 138.0.7204.251
Node.js: 22.19.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 25.0.0

[kdubau]

Thank you for reporting this. As a workaround set this setting in settings.json:

"microsoft-authentication.implementation": "msal-no-broker"

[SapiensID]

Thank you, the workaround worked.

[kdubau]

Let's leave this open as a known issue until it's resolved on our end.