ArcGIS Pro 3.4.2: How to “add field” when working with symbology for raster?

[JamalNUMAN]

ArcGIS Pro 3.4.2: How to “add field” when working with symbology for raster?

For example, in the screenshot below, the “add field” option is not available when working with symbology for raster, whereas it is available when working with vector layers.