I get a php fatal error:
Fatal error: Class ‘acf_field’ not found in …/acf-extras/acf-gallery/gallery.php on line 4
which line contains: “class acf_field_gallery extends acf_field”
my functions.php file contains:
include_once(‘acf-extras/acf-gallery/gallery.php’);
EDIT: the ACF plugin was simply deactivated after update… problem solved by simply reactivating it