When logged in and viewing my own profile only, and only on Meta.SE (so far), the reputation tab is aggregating all reputation earned from a post as if it were a single event. Note (a) the absence of the expander and (b) that it uses the singular, e.g. "+30 upvote" rather than "3 events":
I first noticed this two days ago, but it's apparently not the transient glitch I thought it might be then.
I've seen this in Firefox/Mac, Firefox/Windows, and Chrome/Mac (all browsers up to date and not dev/beta versions). If I use an incognito/private window in Firefox or Chrome I don't see the problem -- and if I then log in, the problem occurs.
Other sites I checked (and are working as expected): Mi Yodeya, Workplace, Writers, Community Building, EL&U, Worldbuilding.
This might be related to Reputation history display is broken in multiple ways, but since the symptoms are different I'm reporting it separately.