I made a wrapper to support this: https://gist.github.com/ayosec/816ccba7a75aba5336db0fe0b9791...
<script>
fetch(".").then(r => console.log(r));
fetch("/").then(r => console.log(r));
</script>
The console show errors when these URLs are loaded: TypeError: NetworkError when attempting to fetch resource. test.html:2:1 if (my_pointer != NULL)
do_stuff(*my_pointer) mozilla::EnableIf<mozilla::IsSame<decltype ((((JS::GCVector<jsid, 0ul, js::TempAllocPolicy>*)((decltype(nullptr))0))->begin)()), decltype ((((JS::GCVector<jsid, 0ul, js::TempAllocPolicy>*)((decltype(nullptr))0))->end)())>::value, void>::Type js::CompartmentChecker::check<JS::GCVector<jsid, 0ul, js::TempAllocPolicy> >(JS::GCVector<jsid, 0ul, js::TempAllocPolicy> const&)