Calendar-day offset between two dates in the user's local timezone.
0 = same calendar day, 1 = b is the calendar day immediately after a,
-1 = b is the previous calendar day, and so on.
Use this instead of dividing a millisecond delta by 86_400_000 — that
approach treats the next 24 hours as "today" even if the clock has crossed
midnight (e.g. 1 AM tomorrow would falsely register as "today").
Calendar-day offset between two dates in the user's local timezone.
0= same calendar day,1=bis the calendar day immediately aftera,-1=bis the previous calendar day, and so on.Use this instead of dividing a millisecond delta by 86_400_000 — that approach treats the next 24 hours as "today" even if the clock has crossed midnight (e.g. 1 AM tomorrow would falsely register as "today").