See https://github.com/whatwg/webidl/pull/1166 and https://github.com/web-platform-tests/wpt/pull/36123 . Currently Safari Tech Preview appears inconsistent, with keys/values/entries non-enumerable but forEach enumerable, at least for AudioParamMap (a maplike<>).
<rdar://problem/100798576>
Pull request: https://github.com/WebKit/WebKit/pull/6571
Committed 256838@main (559702ad5ccd): <https://commits.webkit.org/256838@main> Reviewed commits have been landed. Closing PR #6571 and removing active labels.