diff --git a/src/pretix/presale/context.py b/src/pretix/presale/context.py
index d6b1ff24b..203361ac2 100644
--- a/src/pretix/presale/context.py
+++ b/src/pretix/presale/context.py
@@ -179,6 +179,7 @@ def _default_context(request):
     ctx['html_page_header'] = "".join(h for h in _html_page_header if h)
     ctx['footer'] = _footer
     ctx['site_url'] = settings.SITE_URL
+    ctx['request_get_items'] = request.GET.items()
 
     ctx['js_datetime_format'] = get_javascript_format_without_seconds('DATETIME_INPUT_FORMATS')
     ctx['js_date_format'] = get_javascript_format_without_seconds('DATE_INPUT_FORMATS')
diff --git a/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar.html b/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar.html
index 9d15cbb8d..0adf14929 100644
--- a/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar.html
+++ b/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar.html
@@ -15,7 +15,7 @@
         </li>
         <li class="text-center">
             <form class="form-inline" method="get" id="monthselform" action="{% eventurl event "presale:event.index" cart_namespace=cart_namespace %}">
-                {% for f, v in request.GET.items %}
+                {% for f, v in request_get_items %}
                     {% if f != "date" %}
                         <input type="hidden" name="{{ f }}" value="{{ v }}">
                     {% endif %}
diff --git a/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar_week.html b/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar_week.html
index 6f331b060..fb53d66e3 100644
--- a/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar_week.html
+++ b/src/pretix/presale/templates/pretixpresale/event/fragment_subevent_calendar_week.html
@@ -15,7 +15,7 @@
         </li>
         <li class="text-center">
             <form class="form-inline" method="get" id="monthselform" action="{% eventurl event "presale:event.index" cart_namespace=cart_namespace %}">
-                {% for f, v in request.GET.items %}
+                {% for f, v in request_get_items %}
                     {% if f != "date" %}
                         <input type="hidden" name="{{ f }}" value="{{ v }}">
                     {% endif %}
diff --git a/src/pretix/presale/templates/pretixpresale/fragment_event_list_filter.html b/src/pretix/presale/templates/pretixpresale/fragment_event_list_filter.html
index f763a54d8..674737ded 100644
--- a/src/pretix/presale/templates/pretixpresale/fragment_event_list_filter.html
+++ b/src/pretix/presale/templates/pretixpresale/fragment_event_list_filter.html
@@ -7,7 +7,7 @@
 {% if filter_form.fields %}
     <form class="event-list-filter-form" method="get" data-save-scrollpos>
         <input type="hidden" name="filtered" value="1">
-        {% for f, v in request.GET.items %}
+        {% for f, v in request_get_items %}
             {% if f not in filter_form.fields and f != "page" %}
                 <input type="hidden" name="{{ f }}" value="{{ v }}">
             {% endif %}
diff --git a/src/pretix/presale/templates/pretixpresale/organizers/calendar.html b/src/pretix/presale/templates/pretixpresale/organizers/calendar.html
index a2b0e4b04..16e1044dd 100644
--- a/src/pretix/presale/templates/pretixpresale/organizers/calendar.html
+++ b/src/pretix/presale/templates/pretixpresale/organizers/calendar.html
@@ -47,7 +47,7 @@
                     </li>
                     <li class="text-center">
                         <form class="form-inline" method="get" id="monthselform" action="{% eventurl request.organizer "presale:organizer.index" %}">
-                            {% for f, v in request.GET.items %}
+                            {% for f, v in request_get_items %}
                                 {% if f != "date" %}
                                     <input type="hidden" name="{{ f }}" value="{{ v }}">
                                 {% endif %}
diff --git a/src/pretix/presale/templates/pretixpresale/organizers/calendar_day.html b/src/pretix/presale/templates/pretixpresale/organizers/calendar_day.html
index 820f07e3f..dbb4dae4b 100644
--- a/src/pretix/presale/templates/pretixpresale/organizers/calendar_day.html
+++ b/src/pretix/presale/templates/pretixpresale/organizers/calendar_day.html
@@ -47,7 +47,7 @@
                     </li>
                     <li class="text-center">
                         <form class="form-inline" method="get" id="monthselform" action="{% eventurl request.organizer "presale:organizer.index" %}">
-                            {% for f, v in request.GET.items %}
+                            {% for f, v in request_get_items %}
                                 {% if f != "date" %}
                                     <input type="hidden" name="{{ f }}" value="{{ v }}">
                                 {% endif %}
diff --git a/src/pretix/presale/templates/pretixpresale/organizers/calendar_week.html b/src/pretix/presale/templates/pretixpresale/organizers/calendar_week.html
index b4077d6d0..c95e4cff6 100644
--- a/src/pretix/presale/templates/pretixpresale/organizers/calendar_week.html
+++ b/src/pretix/presale/templates/pretixpresale/organizers/calendar_week.html
@@ -47,7 +47,7 @@
                     </li>
                     <li class="text-center">
                         <form class="form-inline" method="get" id="monthselform" action="{% eventurl request.organizer "presale:organizer.index" %}">
-                            {% for f, v in request.GET.items %}
+                            {% for f, v in request_get_items %}
                                 {% if f != "date" %}
                                     <input type="hidden" name="{{ f }}" value="{{ v }}">
                                 {% endif %}