把/plugin/xn_tag/hook/post_js.htm内容替换为以下内容即可。

<script>
var forumlist = <?php echo xn_json_encode($forumlist_show);?>;
// 初始化值，选中的值
var tagids = <?php echo xn_json_encode($tagids);?>;
var action = '<?php echo $action;?>';
var jfid = $('select[name="fid"]');
var fid = <?php echo intval($fid); ?> || $('select[name="fid"]').val();
jfid.on('change', function() {
	var fid = jfid.val();
	fid_on_change(fid);
});
function fid_on_change(fid) {
	var s = '';
	var forum = forumlist[fid];
	$.each(forum.tagcatelist, function(k, tagcate) {
		s += '<select class="custom-select mr-1 mb-3 w-auto" name="tagid[]">';
		s += '<option value=0>'+ tagcate.name +'</option>';
		$.each(tagcate.taglist, function(k, tag) {
			s += '<option value='+ tag.tagid + (xn.in_array(tag.tagid, tagids) || (tag.tagid == tagcate.defaulttagid && action == 'selected') ? ' selected' : '') + '>'+ tag.name +'</option>';
		});
		s += '</select>';
		});
	$('#nav_tag_list_div').html(s);
}
fid_on_change(fid);
$('#nav_tag_list_div').on('click', 'a.tag_option', function() {
	var jthis = $(this);
	var tagid = jthis.attr('tagid');
	jthis.toggleClass('active');
	// 隐藏域
	var v = jthis.hasClass('active') ? tagid : '';
	jthis.next().attr('value', v);
});
// tag 选中区域。
</script>​

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