From cd168a2b410f60698e8a7f4a2c0fe9187506cc43 Mon Sep 17 00:00:00 2001
From: Matt Westcott <matt@west.co.tt>
Date: Thu, 29 Oct 2015 12:10:46 +0000
Subject: [PATCH] Skip M2M relations in the field list when copying pages -
 fixes #1852

---
 wagtail/wagtailcore/models.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/wagtail/wagtailcore/models.py b/wagtail/wagtailcore/models.py
index ccdafbcab7..d17517a482 100644
--- a/wagtail/wagtailcore/models.py
+++ b/wagtail/wagtailcore/models.py
@@ -739,6 +739,11 @@ class Page(six.with_metaclass(PageBase, MP_Node, ClusterableModel, index.Indexed
                 if field.auto_created:
                     continue
 
+                # Ignore m2m relations - they will be copied as child objects
+                # if modelcluster supports them at all (as it does for tags)
+                if field.many_to_many:
+                    continue
+
                 # Ignore parent links (page_ptr)
                 if isinstance(field, models.OneToOneField) and field.parent_link:
                     continue