Hello there,
Your browser should save the username and password and nothing to do with kiosk mode.
You may also want to set up automatic logon for your kiosk device. When your kiosk device restarts, from an update or power outage, you can sign in the assigned access account manually. Or, you can configure the device to sign in to the assigned access account automatically. Make sure that Group Policy settings applied to the device don't prevent automatic sign in.
Hope this resolves your Query !!
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