Merge remote-tracking branch 'origin/release-v1.26.0' into matrix-org-hotfixes

1 files changed, 1 insertions, 1 deletions

diff --git a/synapse/util/iterutils.py b/synapse/util/iterutils.py

index 6ef2b008a4..8d2411513f 100644
--- a/synapse/util/iterutils.py
+++ b/synapse/util/iterutils.py
@@ -78,7 +78,7 @@ def sorted_topologically(
         if node not in degree_map:
             continue
 
-        for edge in edges:
+        for edge in set(edges):
             if edge in degree_map:
                 degree_map[node] += 1