I have tried this on Treeherder using the commit prior to ESMification, and it seems like the failures are still reproducible there: https://treeherder.mozilla.org/jobs?revision=4b522eebd571eb0478151efe4c3ca4daca9ad4d4&repo=try
Bug 1791571 Comment 3 Edit History
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I cannot reproduce this failure locally. I have tried this on Treeherder using the commit prior to ESMification, and it seems like the failures are still reproducible there: https://treeherder.mozilla.org/jobs?revision=4b522eebd571eb0478151efe4c3ca4daca9ad4d4&repo=try