`boostThreshold` for one series makes all series boosted.

[ddragula]

Expected behaviour

The boostThreshold option enables boost only for series that have more or equal points amount than the threshold, and series that have less are displayed by default.

Actual behaviour

If there is a series that has more points than the set boostThreshold, all series are displayed in boost mode until one series is toggled off and on, using the legend.

Live demo with steps to reproduce

https://jsfiddle.net/BlackLabel/3beqs7ch/

1. All series are displayed in boost mode.
2. Double-click any legend item twice to disable and enable a series.
3. The scatter series is displayed as it should have been from the beginning.

Product version

Highcharts v10.3.3