If an event does not have a location attached to it, then it does not appear in the map. You can view these events in alternate ways.
When you click on the events in the popup, the metadata information is
displayed just to the left of the timeline. The timeline will not sync with
these events. If there is only one event without a location (e.g. once you
have conducted a search to narrow the results down), the popup will contain
the information of the event instead of a list.
It doesn’t matter if you choose to organize from a - z or z - a, the events
missing a location will always be under "m" for missing.
If you use this method of viewing those events without locations, you cannot
access the description in either the grid or the timeline (from the grid).