Element type ' buttons other ' is not supported with bootstrap theme

First of thing, Thanks for the great module.

My issue is when i use element type "buttons other", the other field is not working.

var $container = $(this).find('.form-radios');

class "form-radios" is not printed when i used bootstrap theme in some reasons.

so we need to change it to be

var $container = $(this).find('.js-webform-webform_buttons');