So with 9.1.2 I'm getting ReferenceError with HC 9.1.2: Can't find variable: Intl. Seems like this new version of highcharts is referencing Intl for the first time? I'm mostly using highcharts in a slightly old browser environment (phantomjs to be precise). Is there a recommended polyfill for Intl so that I can get things up and running with 9.1.2?