The "Invite anyone for feedback" feature is now greyed out , also it worked before and I did not change anything.
We assume that you try to use the function on a diagram located in "My Documents". It was never intended that diagrams from "my Documents" could be shared and the the comment function did not work properly if the diagram was located in this folder. This bug was fixed with the version 13.2 and please move the diagrams to "Shared Documents" to be able to use this function on these diagrams.
KBA , BPI-SIG-CA-SEC-UM-IN , Invitations / License Management for SAP Signavio , How To