Events for annotation and indicator changed
For a StockChart every time the user adds, removes or modifies an annotation or an indicator, either over the annotation-/indicator-popup or by dragging an annotation-control-point directly, an event on the chart instance should be fired, so that you can e.g. automatically save the chart-state every time something has changed.
Maybe something like:
Thank you for submitting the idea.
Basic events are already here: on chart level we have addSeries (https://api.highcharts.com/highcharts/chart.events.addSeries) and series remove – implemented, but not a part of documented API (demo: http://jsfiddle.net/BlackLabel/0cosmk2g/) or similar series destroy (the same situation).
For series update you could use series render event (not a part of documented API).
Events for annotation update are not yet implemented.
How to resolve:
Generally, this could be implemented through extending Highcharts. Related functions that create, update and destroy annotations could be wrapped to fire additional events. I’ll try to provide a POC later this week.