4π
β
The fastest hack would be to replace:
<div style="display: none;">
with
<div style="position:absolute;left:-9999px;top:-9999px;">
and it will work: https://jsfiddle.net/FGRibreau/n1cx9d70/2/ π
PS: If you need to render the chart server-side (e.g. in a batch) in order to then embed it inside PDF reports then you might want to consider dedicated services like Image-Charts.
Source:stackexchange.com