The Citrix Diagnostics Toolkit is a rapid deployment platform that delivers a suite of tools and automation options in an easy to use structured format that closely resembles the look and feel of any standard Windows application, even though each tool is an independent standalone application. By the way, Citrix Receiver 12.9.1 doesn't work for me either under Mojave. It is listed as compatible to MacOs 10.13.
Citrix Receiver is version 12.9.1 for Mac from their website.
Citrix Receiver Diagnostics Tool For Mac Download.
