ReferenceEditor without threshold

The ReferenceEditor (in a node property) has a threshold value.
Can this threshold be omitted?

Current situation
A user clicks in the ReferenceEditor and no entry is loaded. The user has to type two (or at least one) character to make the editor load entries.

Desired behaviour
The user should be able to click in the ReferenceEditor and all possible entries should be visible/selectable without typing.

Is there any way to set the threshold to zero so that all the entries will get loaded, the moment the user clicks on the editor?