Calendar Stuck on Loading after update to 2.13.7

After updating the plugin to 2.13.7, the full calendar gets stuck on loading. I could pinpoint the issue to the file class-eventorganiser-shortcodes.php lines 419 to 432. If I replace those lines to the way it was on version 2.13.6, the calendar loads fine.
Here is the currently code on 2.13.7 and causes the calendar get stuck:

static function print_script() {
if ( ! self::$add_script ) {
return;
}
$terms = get_terms( 'event-category', array( 'hide_empty' => 0 ) );
$fullcal = (empty(self::$calendars) ? array() : array(
'firstDay'=>intval(get_option('start_of_week')),
'venues' => get_terms( 'event-venue', array('hide_empty' => 0)),
'categories' => $terms,
'tags' => get_terms( 'event-tag', array('hide_empty' => 1)),
));

The way it was on 2.13.6 and the calendar loads fine:

static function print_script() {
global $wp_locale;
if ( ! self::$add_script ) return;
$_terms = get_terms( 'event-category', array('hide_empty' => 0));
$terms = array();
while ( $term = array_shift( $_terms ) ){
$terms[$term->term_id] = $term;
}
$fullcal = (empty(self::$calendars) ? array() : array(
'firstDay'=>intval(get_option('start_of_week')),
'venues' => get_terms( 'event-venue', array('hide_empty' => 0)),
'categories' => $terms,
'tags' => get_terms( 'event-tag', array('hide_empty' => 1)),
));

my WP Debug show no errors. The memory limit is set to 256M.
Right now I’m using the way it was on 2.13.6 but I’m afraid it will inherit the issue again with the next update.

Any help is really appreciated!
Thanks.

https://www.ads-software.com/plugins/event-organiser/