Added a workaround for an symfony issue with collectiontype.

src/Form/CollectionTypeExtension.php

@@ -53,7 +53,7 @@ class CollectionTypeExtension extends AbstractTypeExtension
 
     public static function getExtendedTypes(): iterable
     {
-        return [CollectionType::class];
+        return [CollectionType::class, WorkaroundCollectionType::class];
     }
 
     public function configureOptions(OptionsResolver $resolver): void

src/Form/Part/OrderdetailType.php

@@ -47,6 +47,7 @@ use App\Entity\Parts\Supplier;
 use App\Entity\PriceInformations\Orderdetail;
 use App\Entity\PriceInformations\Pricedetail;
 use App\Form\Type\StructuralEntityType;
+use App\Form\WorkaroundCollectionType;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\Extension\Core\Type\CheckboxType;
 use Symfony\Component\Form\Extension\Core\Type\CollectionType;
@@ -109,7 +110,7 @@ class OrderdetailType extends AbstractType
             }
 
             //Attachment section
-            $event->getForm()->add('pricedetails', CollectionType::class, [
+            $event->getForm()->add('pricedetails', WorkaroundCollectionType::class, [
                 'entry_type' => PricedetailType::class,
                 'allow_add' => $this->security->isGranted('@parts_prices.create'),
                 'allow_delete' => $this->security->isGranted('@parts_prices.delete'),

src/Form/Part/PartBaseType.php

@@ -56,6 +56,7 @@ use App\Form\ParameterType;
 use App\Form\Type\MasterPictureAttachmentType;
 use App\Form\Type\SIUnitType;
 use App\Form\Type\StructuralEntityType;
+use App\Form\WorkaroundCollectionType;
 use FOS\CKEditorBundle\Form\Type\CKEditorType;
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\Extension\Core\Type\CheckboxType;
@@ -258,7 +259,7 @@ class PartBaseType extends AbstractType
         ]);
 
         //Orderdetails section
-        $builder->add('orderdetails', CollectionType::class, [
+        $builder->add('orderdetails', WorkaroundCollectionType::class, [
             'entry_type' => OrderdetailType::class,
             'allow_add' => $this->security->isGranted('orderdetails.create', $part),
             'allow_delete' => $this->security->isGranted('orderdetails.delete', $part),

src/Form/WorkaroundCollectionType.php

@@ -0,0 +1,31 @@
+<?php
+
+
+namespace App\Form;
+
+
+use Symfony\Component\Form\AbstractType;
+use Symfony\Component\Form\Extension\Core\Type\CollectionType;
+use Symfony\Component\Form\FormInterface;
+use Symfony\Component\Form\FormView;
+
+/**
+ * This a workaround for the issue #37024.
+ * @package App\Form
+ */
+class WorkaroundCollectionType extends CollectionType
+{
+
+    /**
+     * Use the original implementation for finishView() instead of the one, the one that cause the bug.
+     * @param  FormView  $view
+     * @param  FormInterface  $form
+     * @param  array  $options
+     */
+    public function finishView(FormView $view, FormInterface $form, array $options)
+    {
+        if ($view->vars['prototype']->vars['multipart']) {
+            $view->vars['multipart'] = true;
+        }
+    }
+}