1 files changed, 1 insertions, 1 deletions
diff --git a/testing/web-platform/tests/tools/webtransport/h3/capsule.py b/testing/web-platform/tests/tools/webtransport/h3/capsule.py
index 74ca71ade9..fc8183a65f 100644
--- a/testing/web-platform/tests/tools/webtransport/h3/capsule.py
+++ b/testing/web-platform/tests/tools/webtransport/h3/capsule.py
@@ -108,7 +108,7 @@ class H3CapsuleDecoder:
             if self._final:
                 raise e
             if not self._buffer:
-                return 0
+                return
             size = self._buffer.capacity - self._buffer.tell()
             if size >= UINT_VAR_MAX_SIZE:
                 raise e