Theme bootstrap5 no border on select

image

<select class="form-select" id="category" name="category"> </select>
        $('#category').select2({
            ajax: {
                url: "/Scraper/search-categories",
                dataType: 'json',
                delay: 250,
                placeholder: 'Search by category',
                multiple: true,
                data: function(params) {
                    return {
                        q: params.term, // search term
                        page: params.page
                    };
                },
                processResults: function(data, params) {
                    params.page = params.page || 1;
                    return {
                        results: data.data,
                        pagination: {
                            more: (params.page * 30) < data.total_count
                        }
                    };
                },
                cache: true,
            },
            placeholder: 'Search for a category',
            minimumInputLength: 1,
            templateResult: formatCategory,
            templateSelection: formatRepoSelectionCategory,
            theme: "bootstrap5"
        });

 function formatCategory(repo) {
            if (repo.loading) {
                return repo.text;
            }

            var $container = $(
                "<div class='select2-result-repository clearfix'>" +
                "<div class='select2-result-repository__meta'>" +
                "<div class='select2-result-repository__title'></div>" +
                "</div>" +
                "</div>"
            );
            $container.find(".select2-result-repository__title").text(repo.category_name);
            return $container;
        }
function formatRepoSelectionCategory(repo) {
            return repo.category_name || repo.text;
        }

the select element closed has no border around it, just the placeholder

How do you use select2 with bootstrap 5? I have tried to use it but it comes out very different from the other elements of the DOM, it is not responsive and without the border like yours