Merge pull request #6275 from wenzhixin/fix/6274

fix/6274

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

@@ -584,7 +584,7 @@ BootstrapTable.prototype.initToolbar = function (...args) {
     that.onMultipleSort()
   }
 
-  if (this.options.showMultiSortButton) {
+  if (this.options.showMultiSort && this.options.showMultiSortButton) {
     this.buttons = Object.assign(this.buttons, {
       multipleSort: {
         html: Utils.sprintf(theme.html.multipleSortButton,