Symptom
on ISE 3.1 and 3.0 when tried to add an Anew portal tag with a special character under the portal certificate it will be accepted and then when trying to move it to another certificate it failed with the error:
You have entered text that appears to contain unsupported tags or markup language. Remove those characters and try again.
Conditions
Select an excited portal tag contain special character
Workaround
Add the portal tag as new one and re-type it (don't select it from the list)
Further Problem Description
issue re-predoucble on the lab with ISE 3.1 and 3.0