Open in new tab). if ( class_exists( 'acf_revisions' ) ) { // Reference to ACF's acf_revisions class // We need this to target its method, acf_revisions::acf_validate_post_id $acf_revs_cls = \acf()->revisions; // This hook is added the ACF file: includes/revisions.php:36 (in ACF PRO v5.11) remove_filter( 'acf/validate_post_id', array( $acf_revs_cls, 'acf_validate_post_id', 10 ) ); }