Specifically it appears it is bug 1777287 and the exposure of the OffscreenCanvasRenderingContext2D text APIs.
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Specifically it appears it is bug 1777287 and the exposure of the OffscreenCanvasRenderingContext2D text APIs. If I stop exposing it on WebIDL, but leave the other changes, it passes: https://treeherder.mozilla.org/jobs?repo=try&revision=2ed9b2160e94f32bfe123e2d5466ac207e27dfd8 https://hg.mozilla.org/try/rev/cc05a51902d9fc658c0f06ba012970fdedc9df25