HighStockchart gui default line annotation color "black". i need to change this color to "blue" color. when using dark theme in highstock chart its difficult to identify black color line. how can I change this color default to "blue" without manually changing it.
https://www.highcharts.com/demo/stock/stock-tools-gui/dark-unica

You can set stroke for all annotations:
or specify
annotationsOptionsonly forsegment:Live demo: https://jsfiddle.net/BlackLabel/14qt9Le0/
API Reference: https://api.highcharts.com/highstock/navigation.bindings.segment