This was intentional and suggested by emilio iirc, not sure if we want to keep this or not. Spec doesn't say much on this specifically. Chromium they don't do this afaik.
Bug 1844541 Comment 6 Edit History
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This was intentional and suggested by emilio iirc, not sure if we want to keep this or not. Spec doesn't say much on this specifically. Chromium don't do this afaik.