diff --git a/scripts/xkcd/xkcd.py b/scripts/xkcd/xkcd.py
index d8e41cb..b339f5c 100755
--- a/scripts/xkcd/xkcd.py
+++ b/scripts/xkcd/xkcd.py
@@ -29,7 +29,7 @@ for n in range(START_NUMBER, END_NUMBER + 1):
     assert n == data['num']
 
     image_extension = Path(data['img']).suffix.lower()
-    assert image_extension in [ '.jpg', '.jpeg', '.png' ]
+    assert image_extension in [ '.jpg', '.jpeg', '.png', '.gif' ]
 
     node_id = f"xkcd_comic_{n}"