I am experiencing the similar problem since 2.3.4 and now with 2.3.5. I have one reccuring event and before version 2.3.4 I used to have 1 past event and 3 upcoming events displayed in the widget. With 2.3.4 widget started showing numerous occurrences in the future. For the time I fixed it by switching to 0 events in the past with which it showed correct number of events in the future.
With 2.3.5 today the problem is back but now my old solution is not working.
Show today’s events tick seems not to have any influence.
0 events in the past and 0 events in the future – shows nothing
1 event in the past and 0 events in the future – shows 1 in the past
0 events in the past and 1 event in the future – shows 1 in the future
1 event in the past and 1 event in the future – shows 1 in the past and 16 in the future
0 events in the past and 2 events in the future – shows 0 in the past and 17 in the future
and so on
