* Fix the display of missing lists

See #6786 -- this fixes part of the issue pertaining to lists that don't exist. I copied the Column being returned from the missing status logic, which works fine. Prior to this, the missing lists logic would generate a column with no back button and with a broken layout. This doesn't fix the broken display of missing accounts -- the column construction pertaining to that logic happens in multiple external functions.

* import ColumnBackButton

missed the import with the first commit