Chart Tooltip shows random value

Hi,
I’ve noticed that on mouse over of the chart, the tooltip shows a random internally generated value eg. chart 0,chart 1 etc,…
how do we control the same?
just mouse over the blank area inside the chart in the below link:
https://docs.webix.com/samples/08_chart/05_line_chart/02_style.html

A static title the accessibility-related requirement.

Charts are rendered with the help of HTML canvas.
Currently, each canvas object within a chart has title as ariaLabel+index.
Default ariaLabel is a view name (“chart”), the index corresponds to chart series (0 for a 1st / single set of rendered values).

We agree that such structure of the title can be a bit confusing, so we will consider the improvement.