Disable button form on submit.

public/js/ff/firefly.js

@@ -15,6 +15,11 @@ $(function () {
 
     configAccounting(currencySymbol);
 
+    // on submit of form, disable any button in form:
+    $('form.form-horizontal').on('submit',function(e) {
+        $('button[type="submit"]').prop('disabled',true);
+    });
+
     $.ajaxSetup({
                     headers: {
                         'X-CSRF-Token': $('meta[name="_token"]').attr('content')