When creating (or adding values to) a coded value domain in ArcGIS Pro 2.4.1 (and the previous versions), adding new coded values is awkward. After adding one row and hitting ENTER, the next row is highlighted but you have to select the cell to start typing -- an extra, awkward click, especially if you are adding many values. Please make it like ArcMap where you enter one row, hit enter, and you can start typing on the next row immediately. (This is a similar issue to the problem with attribute table editing before 2.4)
Current workaround is to use tabs; ENTER should work the same way!