Thankyou for posting your query on Microsoft Q&A, from above description I could understand that you want sign-out to occur without prompting the user to select an account.
Please do correct me if this is not the case by responding in the comments section.
You may use option claim logout_hint
To use
logout_hint
, enable thelogin_hint
optional claim in your client application and use the value of thelogin_hint
optional claim as thelogout_hint
parameter. Don't use UPNs or phone numbers as the value of thelogout_hint
parameter.
Thanks,
Akshay Kaushik
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