Fixed infinite redirect

app/views/blazer/_variables.html.erb

@@ -20,7 +20,12 @@
         <%= text_field_tag var, params[var], style: "width: 120px; margin-right: 20px;", autofocus: i == 0 && !var.end_with?("_at") && !params[var], class: "form-control" %>
         <% if var.end_with?("_at") %>
           <script>
-            $("#<%= var %>").daterangepicker({singleDatePicker: true, locale: {format: "YYYY-MM-DD"}});
+            $("#<%= var %>").daterangepicker({singleDatePicker: true, locale: {format: "YYYY-MM-DD"}, autoUpdateInput: false});
+            // hack to start with empty date
+            $("#<%= var %>").on("apply.daterangepicker", function(ev, picker) {
+              $(this).val(picker.startDate.format("YYYY-MM-DD"));
+              $(this).change();
+            });
           </script>
         <% end %>
       <% end %>