Interaction for modifying feature geometries. To modify features that have
been added to an existing source, construct the modify interaction with the
source option. If you want to modify features in a collection (for example,
the collection used by a select interaction), construct the interaction with
the features option. The interaction must be constructed with either a
source or features option.
By default, the interaction will allow deletion of vertices when the alt
key is pressed. To configure the interaction with a different condition
for deletion, use the deleteCondition option.