Append(m1):Append(m2) Hidden(m1):Viewable(m2)
- foobar_m2 should be on the far right
- foobar_m1 should be on direct left of foobar_m2
- both foobar_m1 and foobar_m2 should be in the column picker for this page
- only foobar_m2 should be in the column picker for the main library