I ran into this on my local stack which is a bit ahead of whats in central, and so the linked test case needs Response. I'll try to to rescue the test case from Bug 1503324. Regarding response-stream-with-broken-then.any.js, all sub-tests fail.
Bug 1736460 Comment 6 Edit History
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I ran into this on my local stack which is a bit ahead of whats in central, and so the linked test case needs Response. I'll try to to rescue the test case from Bug 1503324. Regarding response-stream-with-broken-then.any.js, all sub-tests fail by allowing substitution.