Action: mc_location_controller

do_action( 'mc_location_controller', $option, $fieldname, $selected, $context )

Filter the string of <option> elements inside the <select> input used for a controlled location field.

Parameters:
Name Type Description
$option string

An HTML string of

$fieldname string

The field being generated.

$selected string

The selected value for this location.

$context string

Whether this is being edited in a location or an event context.

Source: