fix: is popup lost on filter (#868) (#869)

Author: PavelPancocha

src/unfold/admin.py

@@ -7,6 +7,7 @@
 from django.contrib.admin import StackedInline as BaseStackedInline
 from django.contrib.admin import TabularInline as BaseTabularInline
 from django.contrib.admin import display, helpers
+from django.contrib.admin.options import IS_POPUP_VAR, TO_FIELD_VAR
 from django.contrib.admin.widgets import RelatedFieldWidgetWrapper
 from django.db import models
 from django.db.models import BLANK_CHOICE_DASH, Model
@@ -472,7 +473,14 @@ def changelist_view(
             for action in self.get_actions_row(request)
         ]
 
-        extra_context.update({"actions_list": actions, "actions_row": actions_row})
+        extra_context.update(
+            {
+                "actions_list": actions,
+                "actions_row": actions_row,
+                "to_field_var": TO_FIELD_VAR,
+                "is_popup_var": IS_POPUP_VAR,
+            }
+        )
 
         return super().changelist_view(request, extra_context)
 

src/unfold/templates/unfold/change_list_filter.html

@@ -45,6 +45,15 @@ <h3 class="border-b flex font-semibold mb-4 px-4 py-4 text-font-important-light
                         {% if request.GET.o %}
                             <input type="hidden" name="o" value="{{ request.GET.o }}">
                         {% endif %}
+
+                        {% if is_popup %}
+                            <input type="hidden" name="{{ is_popup_var }}" value="1">
+                        {% endif %}
+
+                        {% if to_field %}
+                            <input type="hidden" name="{{ to_field_var }}" value="{{ to_field }}">
+                        {% endif %}
+
                 {% endif %}
 
                 {% for spec in cl.filter_specs %}