diff --git a/wrap/python/tests/ipnbdoctest.py b/wrap/python/tests/ipnbdoctest.py
index 4bcea3f5a..216c5c4d4 100755
--- a/wrap/python/tests/ipnbdoctest.py
+++ b/wrap/python/tests/ipnbdoctest.py
@@ -70,10 +70,13 @@ def sanitize(s):
     # SVG generated by graphviz may put note at different positions
     # depending on the graphviz build.  Let's just strip anything that
     # look like a position.
-    s = re.sub(r'<path d="[^"]*"', '<path', s)
-    s = re.sub(r'x="[0-9.]+"', 'x=""', s)
-    s = re.sub(r'y="[0-9.]+"', 'y=""', s)
-
+    s = re.sub(r'<path[^/]* d="[^"]*"', '<path', s)
+    s = re.sub(r'points="[^"]*"', 'points=""', s)
+    s = re.sub(r'x="[0-9.-]+"', 'x=""', s)
+    s = re.sub(r'y="[0-9.-]+"', 'y=""', s)
+    s = re.sub(r'width="[0-9.]+pt"', 'width=""', s)
+    s = re.sub(r'height="[0-9.]+pt"', 'height=""', s)
+    s = re.sub(r'viewBox="[0-9 .-]*"', 'viewbox=""', s)
     return s
 
 
@@ -102,17 +105,18 @@ def compare_outputs(test, ref, skip_cmp=('png', 'traceback',
         if key not in test:
             print("missing key: %s != %s" % (test.keys(), ref.keys()))
             return False
-        elif key not in skip_cmp and sanitize(test[key]) != sanitize(ref[key]):
-            print("mismatch %s:" % key)
-            exp = ref[key]
-            eff = test[key]
-            if exp[:-1] != '\n':
-                exp += '\n'
-            if eff[:-1] != '\n':
-                eff += '\n'
-            print(''.join(diff(exp.splitlines(1), eff.splitlines(1),
-                               fromfile='expected', tofile='effective')))
-            return False
+        elif key not in skip_cmp:
+            exp = sanitize(ref[key])
+            eff = sanitize(test[key])
+            if exp != eff:
+                print("mismatch %s:" % key)
+                if exp[:-1] != '\n':
+                    exp += '\n'
+                if eff[:-1] != '\n':
+                    eff += '\n'
+                print(''.join(diff(exp.splitlines(1), eff.splitlines(1),
+                                   fromfile='expected', tofile='effective')))
+                return False
     return True
 
 def _wait_for_ready_backport(kc):