We should implement https://github.com/tc39/ecma262/pull/2600
<rdar://problem/127999027>
Sosuke, I'm 90% sure I had a patch somewhere ready, please allow me a few days to find it 😊
Ahh sorry, I've already created the PR( https://github.com/WebKit/WebKit/pull/28171 ). The local commit hook didn't work well and I couldn't comment to bugzilla.