Fixed showFooter display bug after resize table width

src/bootstrap-table.js

@@ -2074,6 +2074,8 @@ class BootstrapTable {
     const $ths = this.$tableFooter.find('th')
     let $tr = this.$body.find('>tr:first-child:not(.no-records-found)')
 
+    $ths.find('.fht-cell').width('auto')
+
     while ($tr.length && $tr.find('>td[colspan]:not([colspan="1"])').length) {
       $tr = $tr.next()
     }

src/extensions/multiple-sort/bootstrap-table-multiple-sort.js

@@ -385,7 +385,7 @@ const bootstrap = {
                 </div>
                 <div class="mt-30">
                     <button type="button" class="btn" data-close>%s</button>
-                    <button type="button" class="btn multi-sort-order-button" data-close>%s</button> 
+                    <button type="button" class="btn multi-sort-order-button" data-close>%s</button>
                 </div>
             </div>
           </div>
@@ -816,7 +816,7 @@ BootstrapTable.prototype.setButtonStates = function () {
 
 BootstrapTable.prototype.multiSort = function (sortPriority) {
   this.options.sortPriority = sortPriority
-  this.options.sortName = ''
+  this.options.sortName = undefined
 
   if (this.options.sidePagination === 'server') {
     this.options.queryParams = params => {
@@ -829,4 +829,4 @@ BootstrapTable.prototype.multiSort = function (sortPriority) {
   }
 
   this.onMultipleSort()
-}
+}