Formats number according to user's locale

assets/js/src/listing/groups.jsx

@@ -20,7 +20,8 @@ define(['react', 'classnames'], (React, classNames) => {
               href="javascript:;"
               className={classes}
               onClick={this.handleSelect.bind(this, group.name)} >
-              {group.label} <span className="count">({ group.count.toLocaleString() })</span>
+              {group.label}
+              <span className="count">({ parseInt(group.count, 10).toLocaleString() })</span>
             </a>
           </li>
         );

assets/js/src/listing/pages.jsx

@@ -168,8 +168,9 @@ define([
         numberOfItemsLabel = MailPoet.I18n.t('numberOfItemsSingular');
       } else {
         numberOfItemsLabel = MailPoet.I18n.t('numberOfItemsMultiple')
-            .replace('%$1d', this.props.count.toLocaleString());
+          .replace('%$1d', parseInt(this.props.count, 10).toLocaleString());
       }
+
       return (
         <div className={classes}>
           <span className="displaying-num">{ numberOfItemsLabel }</span>