Tooltip dissapearing and pointer bouncing on line chart mouse move

[rozxter1]

Description

When cursor is over line, close to it, below it - it lose focus randomly on data and drops marker to zero and tooltip is not visible. this is not happening if cursor is over line chart.

Tested on latest Chrome and Firefox

Steps to Reproduce

1. move cursor close to chart line or below it
2. it will hide tooltip randomly and drop pointer to zero Y value

Expected Behavior

Show tooltip even cursor is howering line or is below it

Actual Behavior

Tooltip is flashing, marker element is bouncing to 0 y value

Screenshots

Test 1 - bouncing in one side and other when close to line or below it, but fine when its above

Test 2 - bouncing in another place and keeps bouncing while going more far away from line

Reproduction Link

https://codepen.io/tzioo/pen/MWNqwXP