After upgrading to Manufacturing Apps 8.4 when i choose a property to edit from the additional properties menu I get the following error.
Error invoking service: Unable to Invoke Service GetAdditionalPropertyUI on PTC.SCA.SCO.ManageResourceUtils : null
I am trying to reproduce your issue.
Can you give me some more information about your environment, please.
Database, tomcat version, java version?
From which version of Thingworx did you upgraded?
Did you follow the MFG App upgrade guide?
Installation Guide page 11.
I upgraded from 8.3.2 to 8.4.0 and don`t see the issue you describe.