t box has rounded corners.
Flipping between horizontal and vertical layouts is done by nesting
fields in braces "{...}". The top-level orientation in a record is
horizontal. Thus, a record with label "A | B | C | D" will have 4 fields 
oriented left to right, while "{A | B | C | D}" will have them 
from top to bottom and "A | { B | C } | D" will have "B" over "C", with
"A" to the left and "D" to the right of "B" and "C".
<P> 
The initial orientation of a record node depends on the
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