Bootstrap 4 dom bug

lapegunta

When I use a default datatables viewer whitout define "dom" string the table head and foot appear with classes:
row .col-sm-12 .col-md-6
but when I define a "dom" string, the wrapper row .col-sm-12 .col-md-6 classes seems that are not applied and the buttons, search and pagination adds appear in different lines because not inline "row" class is applied.

Without bootstrap 4 style seems that inline equivalent wrapper classes remains active.

lapegunta

I answer myself.
Although the dom documentation has not been clear to me, I have finally got to include the buttons keeping the default format replacing the default syntax:
"dom": 'Blftrip',

by the formated syntax:
"dom": "<'row mb-2'<'col-12 text-right'B>>" + "<'row'<'col-sm-6'l><'col-sm-6'f>>" + "<'row'<'col-sm-12'tr>>" + "<'row'<'col-sm-5'i><'col-sm-7'p>>",