Update src/playground/addon-settings.jsx

src/playground/addon-settings.jsx

@@ -13,6 +13,8 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
+import 'core-js';
+import 'regenerator-runtime/runtime';
 
 import React from 'react';
 import ReactDOM from 'react-dom';