These docs are for an old release. Info on upgrading to version 2/3
edit doc

editable 1.3

Determines whether the events on the calendar can be modified.

Boolean, default: false

This determines if the events can be dragged and resized. Enables/disables both at the same time. If you don’t want both, use editable in conjunction with eventStartEditable and eventDurationEditable.

This option can be overridden on a per-event basis with the Event Object editable property. However, Background Events can not be dragged or resized.

Prior to version 1.3, the draggable option was used instead.