NTLM auth. request while using Kerberos

User can surf with kerberos auth (member of allowed AD group) some minutes.

Then stoppt it with this request:

https://firewall.fqdn:8091/ntlmauth.html?2www.google.de

and empty page.

AD SSO is active.

No STAS, no Sophos endpoint.

Browser Edge.

Restart the browser lets work again until the next break.