The "timeline-mark-leaves" setting:

Determine whether or not leaf check-ins are marked as such in the details section of the timeline. The value is an integer between 0 and 2:

0

Do not show any special marking for leaf check-ins.

1

Show just "leaf" or "closed"

2

Show "Leaf" or "Closed-Leaf" with emphasis

The default is currently 1. Prior to 2025-10-19, the default was 2. This setting has no effect on the "Classic" view, which always behaves as if the setting were 2.