Please consider decoupling the tooltip and crosshair. Draw crosshairs according to mouse movement inside the plot area. Raise tooltip events when hover occurs in the vicinity of a point; or, in the case of shared tooltip, when the crosshair intersects with series data.

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Reason: Currently, the crosshair is not displayed until the cursor moves close to a point. This is undesirable behaviour to our users who expect the crosshairs to appear as soon as cursor enters the plot area. The bug has been reported to us as "a delay in showing the crosshairs".

The shared crosshair behaves better in that the crosshairs are shown whenever they intersect data, but we do not wish to use the shared option because we want the tooltip to be specific to a point. We are conditionally displaying the tooltip when the cursor is close to a Highstock flag.

From a design perspective... the purpose of a crosshair is to inspect the axis, and the purpose of a tooltip is to inspect a feature on the chart (point, group of points, flag, series, etc.). Since they serve different purposes, they should be separately customizable features.

From a performance/responsiveness perspective, it also makes sense to decouple the crosshairs from the tooltips. Tooltip rendering can impact the responsiveness of the crosshair. It seems that users tolerate tooltip delay better than crosshair delay.