hey! i am facing this issue while using doughnut and pie charts.
If i keep on decreasing the size of window, at certain ranges of window width some of the indexlabels disappear.
for example 416-418 px width 4 out of 5 indexlabels are visible and similarly for other ranges one or more labels disappear. Range is quite small, i agree but unfortunately my mobile phone’s screen falls in one of those width range.
You can even check it on your own link
https://canvasjs.com/html5-javascript-pie-chart/
If you decrease width below 375px, firstly one indexlabel will disappear then 2 and under 330px only yahoo is visible…