Issue #3166653 by raystuart, MattDanger, zoiosilva, newswatch, jcnventura:...

Issue #3166653 by raystuart, MattDanger, zoiosilva, newswatch, jcnventura: [PHP 7.4] Notice: Trying to access array offset on value of type null in linked_field_field_attach_view_alter()

linked_field.module

@@ -331,10 +331,10 @@ function linked_field_field_attach_view_alter(&$output, $context) {
     }
     // Otherwise we use the 'default' view mode.
     else {
-      $display = $instance['display']['default'];
+      $display = isset($instance['display']['default']) ? $instance['display']['default'] : array();
     }
 
-    $settings = $display['settings'];
+    $settings = isset($display['settings']) ? $display['settings'] : array();
 
     // We need special behavior for Display Suite fields.
     if ($element['#field_type'] == 'ds') {