I used ArcGIS Pro (2.1.1) to import a complete *.mxd authored in 10.3 or 10.4. The *.mxd's layout converted just fine as did the data frame; however, 2 pieces of dynamic text did not register in the Drawing Order pane of the Layout tab. If you try to move them, they retract...you cannot delete them and they export. Can anyone testify? Any ideas?