scrollablePlotArea mask opacity with breadcrumbs and zIndex

[kamil-musialowski]

Expected behaviour

Highcharts scrollbar and breadcrumbs should be on top of scrollablePlotArea mask.

Actual behaviour

Live demo with steps to reproduce

https://jsfiddle.net/BlackLabel/fnt5u0eh/

Product version

Highcharts + drilldown 10.3.1 (latest)

Affected browser(s)

Due to the styling, the scrollbar issue might be visible only in Windows.

[karolkolodziej]

The breadcrumbs class should be added to the fixedSelectors- demo.