Vertical line markers with ToolTip
I would like to add vertical line markers to mark for events which happened during the time-series data (like device reboot, device Update, Connected/Disconnected). Like flags from Highstock, just without any label associated and line going from top to bottom. With axis flags it is hard to precisely see when the event occurred when having multiple series plotted. And because the event is for multiple series all together, it is not reasonable to put them onto a particular series.
You mean like plot lines? http://api.highcharts.com/highcharts#xAxis.plotLines