Insertion and drag of stock annotation failure when there are null points.

[vazonik]

Expected behaviour

The annotation is inserted exactly at the mouse click, and the annotation does not "escape" when dragging.

Actual behaviour

The annotation is added slightly next to the place of clicking the mouse on the chart, the sliding causes the annotation to "escape" to the left.

Live demo with steps to reproduce

https://jsfiddle.net/BlackLabel/5a379snx/

1. Draw a circle (Use the Add Circle button)
2. Move the circle

Product version

Highcharts v11.1.0

---

The issue is closely related to regression reported as #18459, but it seems that it has not been fully solved. Interestingly, this workaround solves the problem.

Workaround demo: https://jsfiddle.net/BlackLabel/dyhf4csx/