No connection to another tenant sandbox possible with prerelease VSIX

1. Describe the bug
When the new vsCodeAuthentication setting is activated, we can not connect to sandboxes outside of our tenant. It does not matter if debugging, or downloading symbols. Always getting an error.

This is happening for a lot of developers, see https://engage.cloud.microsoft/main/org/microsoft.com/threads/eyJfdHlwZSI6IlRocmVhZCIsImlkIjoiMzc4Mjc5MzY1MTE4MzYxNiJ9?trk_copy_link=V2

2. To Reproduce
Steps to reproduce the behavior:

1. Get the newest prerelease version 18.0.2242655
2. Add launch config for a tenant outside of your own tenant to your launch.json
3. Download symbols/start debugging for this config

3. Expected behavior
It should download symbols/start debugging successful.

4. Actual behavior

Getting the following error:

[2026-03-27 16:01:33.47] Sending request to https://api.businesscentral.dynamics.com/v2.0/Sandbox/dev/packages?publisher=Microsoft&appName=System&versionText=18.0.0.0&appId=<appid>&tenant=<tenantid>
[2026-03-27 16:01:33.60] Error: Not Found
[2026-03-27 16:01:33.60] Error: Error: An error occured while processing the request.
Request ID: 0d8a5759-9a70-40ac-a13e-f8692e639b2d
Session ID: a6223caa-f148-4a10-8465-2e622c6718d4

5. Versions:

• AL Language: 18.0.2242655

Workaround

Disable feature with "al.useVsCodeAuthentication": false in user config

Internal work item: AB#629348

Start by reproducing the issue with the AL Language prerelease 18.0.2242655, a launch.json configuration for another tenant, and al.useVsCodeAuthentication enabled. Compare symbol download and debugging behavior with the setting disabled; done means both operations work against an external tenant without the Not Found error.