Unable to view entire field name of a map or feature service in Portal for ArcGIS while configuring a pop-up on a web map if the characters of the field exceed 28.
This defect was logged against a version of the software which is no longer supported. The issue is not reproducible in newer versions of ArcGIS Enterprise. If experiencing this behavior, please reach out to Esri Support Services as a new reproduction case is needed to continue investigation.