Redirect directly to time machine page after session transfer

src/pretix/control/templates/pretixcontrol/event/transfer_session.html

@@ -1,6 +1,6 @@
 {% load eventurl %}
 {% load static %}
-<form action="{% eventurl request.event "presale:event.auth" %}" method="post">
+<form action="{% eventurl request.event "presale:event.auth" %}{% if request.GET.next %}?next={{ request.GET.next }}{% endif %}" method="post">
     <input type="hidden" value="{{ new_session }}" name="session">
     <button type="submit">
         Continue

src/pretix/presale/templates/pretixpresale/event/base.html

@@ -135,12 +135,14 @@
                     </p>
                 {% elif request.event_domain or request.organizer_domain %}
                     <p>
-                        {% url "control:event.transfer_session" event=event.slug organizer=event.organizer.slug as time_machine_link %}
-                        {% blocktrans trimmed with time_machine_link=time_machine_link %}
-                        {% absmainurl "control:event.transfer_session" event=event.slug organizer=event.organizer.slug as time_machine_link %}
-                            To view your shop at different points in time, you can enable
-                            <a href="{{ time_machine_link }}"><span class="fa fa-clock-o" aria-hidden="true"></span>time machine</a>.
-                        {% endblocktrans %}
+                        {% absmainurl "control:event.transfer_session" event=event.slug organizer=event.organizer.slug as transfer_session_link %}
+                        {% eventurl event "presale:event.timemachine" as time_machine_link %}
+                        {% with time_machine_link_encoded=time_machine_link|urlencode %}
+                            {% blocktrans trimmed with time_machine_link=transfer_session_link|add:"?next="|add:time_machine_link_encoded %}
+                                To view your shop at different points in time, you can enable
+                                <a href="{{ time_machine_link }}"><span class="fa fa-clock-o" aria-hidden="true"></span>time machine</a>.
+                            {% endblocktrans %}
+                        {% endwith %}
                     </p>
                 {% endif %}
             </div>

src/pretix/presale/views/event.py

@@ -56,6 +56,7 @@ from django.shortcuts import get_object_or_404, redirect, render
 from django.utils.decorators import method_decorator
 from django.utils.formats import get_format
 from django.utils.functional import SimpleLazyObject
+from django.utils.http import url_has_allowed_host_and_scheme
 from django.utils.timezone import get_current_timezone, now
 from django.utils.translation import gettext_lazy as _, pgettext_lazy
 from django.views import View
@@ -924,7 +925,12 @@ class EventAuth(View):
                 raise PermissionDenied(_('Please go back and try again.'))
 
         request.session['pretix_event_access_{}'.format(request.event.pk)] = parent
-        return redirect_to_url(eventreverse(request.event, 'presale:event.index'))
+
+        if "next" in self.request.GET and url_has_allowed_host_and_scheme(
+                url=self.request.GET.get("next"), allowed_hosts=request.host, require_https=True):
+            return redirect_to_url(self.request.GET.get('next'))
+        else:
+            return redirect_to_url(eventreverse(request.event, 'presale:event.index'))
 
 
 class TimemachineForm(forms.Form):