I could also reproduce this issue in latest Nightly, but got a different regressor: bug 1709405. Daisuke, could you please take a look? Thank you!
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I could also reproduce this issue in latest Nightly, but got a different regressor: bug 1709405. Daisuke, could you please take a look? Thank you! https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=2d291a99004dd0aea5304bb8cae306a47083ff94&tochange=3350b68026ed51868a2100acb87d1833d61ac486