Don't list all threads to filter posts by

boards/admin.py

@@ -7,7 +7,7 b' from django.utils.translation import uge'
 class PostAdmin(admin.ModelAdmin):
 
     list_display = ('id', 'title', 'text')
-    list_filter = ('pub_time', 'thread_new')
+    list_filter = ('pub_time',)
     search_fields = ('id', 'title', 'text')
     exclude = ('referenced_posts', 'refmap')
     readonly_fields = ('poster_ip', 'thread_new')