I found a problem with the DrawObjects collection:
The chart has not drawing objects, only bars. In this moment this.DrawObjects.Count == 0 (it's ok).
I draw one horizontal line. In this moment this.DrawObjects.Count == 1 (it's ok).
I do double-click on the horizontal line and I change the Tag of the line (in Data tab).
In this moment this.DrawObjects.Count == 2 !!! (I think is a bug)
Then in the drawing menu I click on Removing Drawing Objects and the horizontal line is removed. The chart is empty, but this.DrawObjects.Count == 1 !!! (other bug)
Regards

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