Append(o1):Append(o2) Viewable(o1):Hidden(o2)
- foobar_o2 should be on the far right
- foobar_o1 should be on direct left of foobar_o2
- both foobar_o1 and foobar_o2 should be in the column picker for this page
- only foobar_o1 should be in the column picker for the main library
- BUG: splitters to the right of foobar_o1 are not resizable - bug XXXXX