JAVASCRIPT

select2 clear options

Remove the selected options : 
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$('#mySelect2').val(null).trigger('change');

============================================

Completly remove the select2 initialization :
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$('#payment_method').html('').select2({data: [{id: '', text: ''}]});

jquery clear select 2

$('select2element').val(null).trigger("change")

jquery reset select2

$("#customers_select").val('').trigger('change')

select2 clear selected

$("#mySelect2").select2({
    allowClear: true
});

reset select option jquery

$('ClassOrIDName').prop('selectedIndex',0); 
// this works perfectly. just put this in any action and your 1st option should be 'select one item' type

reset select2 jquery | clear select2 option value

$("ClassOrIDName").trigger("change");