The Action item emails "click here" links are routing to the Classic UI instead of the MUX. Is it possible to route to the MUX?
Release : 16.1.3+
The ability to route action items to the MUX was introduced in 16.1.3:
https://techdocs.broadcom.com/us/en/ca-enterprise-software/business-management/clarity-project-and-portfolio-management-ppm-on-premise/16-1-3/release-information/clarity-ppm-release-notes.html#concept.dita_8ebed6ba1fc5de89d746baa8a9be14ef035caa38_ActionItemlinks
MUX Action Items Information