Nice IDP url for testing ADFS
An easy way to verify if ADFS is working properly is the idpinitiatedsignon page:
from which you can easily logon against the actual environment.
Since Windows Server 2016 this is not enabled by default anymore.
You can enable it:
Set-ADFSProperties -EnableIdpInitiatedSignon $True
and disable it back:
Set-ADFSProperties -EnableIdpInitiatedSignon $False
AD FS Diagnostic Module:
References: