Constants.Toplayertype t = {tooltips_have_arrows : [ `No | `Yes_with_length_px of float ];tooltip_offset_px : float;tooltip_show_delay : Core.Time_ns.Span.t;tooltip_hide_grace_period : Core.Time_ns.Span.t;hoverable_tooltip_hide_grace_period : Core.Time_ns.Span.t;popover_default_offset_px : float;popover_with_arrow_default_offset_px : float;popover_with_arrow_default_arrow_length_px : float;}hoverable_tooltip_hide_grace_period should be sufficiently long for the user to move their cursor from the anchor to the tooltip.
If tooltips_have_arrows, tooltip_offset_px should be big enough that the arrow doesn't overlap with the anchor. The same applies to popover_with_arrow_default_offset_px.