In includes/js/scripts.js
line 35
– if ( typeof window.FormData !== ‘function’ ) {
+ if ( typeof window.FormData !== ‘function’ && typeof window.FormData !== ‘object’) {
line 190
– if ( typeof window.FormData !== ‘function’ ) {
+ if ( typeof window.FormData !== ‘function’ && typeof window.FormData !== ‘object’) {
It should work without ajax.
It’s related to the fact that they stop using jquery.forms and replace it with using window.FormData that is not compatible in IE8-9.
