@MarkInsco there Bug logged in the system which will address this issue for Portal users.
BUG-00013868: User is unable to identify or click on Map Viewer with Google Chrome version 89.0.4389.90 or higher for Portal for ArcGIS 10.7.1 or Portal for ArcGIS 10.8 on some machines.
An alternate workaround is to use Edge or Firefox while we wait for the fix.
Shelley Schott
Senior Consultant, Esri Australia