Rollover modifier "snap to nearest"

I have an impulse series chart, and with SciChart v3.x the rollover modifier line would “snap” to the nearest point. Since migrating to v6.5 this no longer happens – only the rollover marker snaps, not the vertical line. Setting UseInterpolation=”False” has no effect.

I’ve only noticed this on the impulse series, and the rollover line does still snap on other types (e.g. line, scatter). I just wanted to check that I’m not missing something, or if there any way to reinstate this snapping behaviour?