Not able to respond to posts within the Feature Announcements sections so following up here. Its worth paying attention to the document that was posted by @AI007 especially around NBAR Validation logic.
NBAR will only work in wifi Networks where all AP's are Wifi6 enabled - you can't mix and match. Likewise with a full-stack/combined network. You also can't have a supported MX running 16.4 and mixed Wifi6 and none Wifi6 AP's as again the validation logic will fail and NBAR won't be enabled.
Darren O'Connor | uccert.co.uk https://www.linkedin.com/in/darrenoconnor/
I'm not an employee of Cisco/Meraki. My posts are based on Meraki best practice and what has worked for me in the field.