Portal - dynamic display of measurement in selected units

GeorgieCassar

In a web map used in Portal for ArcGIS, while placing the points along a line to measure, it dynamically displays (when in rubber band mode) the measurement as per a geodesic calculation.  It only recalculates the measurement to the current projection when the line placement has completed.
This is OK but I find some users read their measurement while in rubber band mode.  Thus getting an innaccurate result. 
I would like the dynamically displayed figure to accord to the currently displayed projection.