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Chart series.destroy() not removing sprites
In my application I have a chart that I reconfigure with different series at runtime based on drill in like actions. When you call chart.setSeries, it hooks up the new series, but the old ones fully destroyed and still show up in the chart.
I created a fiddle that demonstrates the issue: https://fiddle.sencha.com/#fiddle/773
Included at the top is a crude override I created that seems to fix the issue, although I don't know how correct of a fix it really is.