I didn't verify the exact regression range but yes, this bug does seem to be fixed in the latest nightly, and it seems plausible that bug 1534549 would have fixed it.
Bug 1544451 Comment 9 Edit History
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I didn't verify the exact fix range but yes, this bug does seem to be fixed in the latest nightly, and it seems plausible that bug 1534549 would have fixed it.