Issue #3466359 by hctom: Allow computed fields to use Component formatter

src/Plugin/Derivative/EntityFieldSourceDeriverBase.php

@@ -282,7 +282,7 @@ abstract class EntityFieldSourceDeriverBase extends DeriverBase implements Conta
         "fields" => [],
       ];
       foreach ($field_definitions as $field_name => $field_definition) {
-        if (!array_key_exists($field_name, $field_storage_definitions)) {
+        if (!array_key_exists($field_name, $field_storage_definitions) && !$field_definition->isComputed()) {
           continue;
         }
         $item_definition = $field_definition->getItemDefinition();