These docs are for an old release. Info on upgrading to v4
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displayEventEnd

Whether or not to display an event’s end time.

Boolean, default:

false // for month and basicWeek views
true  // for agendaWeek, agendaDay, and basicDay

As noted above, each view has a specific default. Get fine-tuned control with View-Specific Options. A single boolean alone will set the value for all views.

If an event does not have an end date/time, or displayEventTime is false, it won’t be displayed anyway, regardless of this setting.