Show "Upcoming Events" in all categories

By default, the event list only returns the events for the current category. There is a value transformer (discourse-calendar-upcoming-events-show-cross-category) that you can use to change that.

You create a new theme component (I think it’s better when it’s loaded early, so use something like “aaa all events in each category” for the name).

In the JS tab, add this:

api.registerValueTransformer(
   "discourse-calendar-upcoming-events-show-cross-category",
   () => true
 );

So it looks like this:

Then save the code, and after a reload, you should be able to see all events in each category.

Screenshots from my testing:
The documentation category with all 3 events


And the same events also visible in the Test 3 category