Showed up in https://github.com/w3c/web-platform-tests/pull/7488
If an interface is further extended by extension specifications, you may find more properties in the toJSON output than expected by the base specification. Best would be to ignore unknown entries in the toJSON serialization.
http://w3c-test.org/resource-timing/idlharness.html rightfully fails on Firefox58 (missing workerStart) and rightfully passes on Chrome 63 (extra serverTiming). Yoohoo!
Thanks @tobie
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http://w3c-test.org/resource-timing/idlharness.html rightfully fails on Firefox58 (missing workerStart) and rightfully passes on Chrome 63 (extra serverTiming). Yoohoo!
Thanks @tobie