There's an issue with the GitHub login to use Copilot in SSMS 22. When attempting to sign into GitHub on our domain the login page opened just shows a spinning wheel around a GitHub logo. The root issue appears to be this. A WDAC policy forbids this dll from running.
Code Integrity determined that a process (\Device\HarddiskVolume12\Windows\Microsoft.NET\Framework64\v4.0.30319\mscorsvw.exe) attempted to load \Device\HarddiskVolume12\Program Files\Microsoft SQL Server Management Studio 22\Release\Common7\IDE\CommonExtensions\Microsoft\OpenTelemetry\Client\OpenTelemetry.Api.dll that did not meet the Microsoft signing level requirements.
The sign in process uses Microsoft Edge WebView. This needs to be changed to a trusted process.