Here is one issue where I saw some comments on the broken Map implementation: https://github.com/google/traceur-compiler/issues/1810 https://github.com/google/t

Here is one issue where I saw some comments on the broken Map implementation: https://github.com/google/traceur-compiler/issues/1810 https://github.com/google/traceur-compiler/issues/1810 Admittedly, this is an older browser at this point (Safari 11 formally shipped yesterday), but I remember it biting a workplace I was at 2 1/2 years ago & we had to polyfill Map and Set. I believe this was fixed in Safari 9. I would like to report it on GitHub, but unfortunately I think it would violate my employment contract until I complete the process to get approval to do open source work.