diff --git a/src/Entity/Attachments/AttachmentType.php b/src/Entity/Attachments/AttachmentType.php
index c99ac392..5b7ca60f 100644
--- a/src/Entity/Attachments/AttachmentType.php
+++ b/src/Entity/Attachments/AttachmentType.php
@@ -63,6 +63,10 @@ class AttachmentType extends AbstractStructuralDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: AttachmentTypeAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, AttachmentTypeParameter>
      */
     #[Assert\Valid]
@@ -70,9 +74,6 @@ class AttachmentType extends AbstractStructuralDBElement
     #[ORM\OrderBy(['group' => 'ASC', 'name' => 'ASC'])]
     protected Collection $parameters;
 
-    /**
-     * @var Collection<Attachment>
-     */
     /**
      * @var Collection<Attachment>
      */
diff --git a/src/Entity/Base/MasterAttachmentTrait.php b/src/Entity/Base/MasterAttachmentTrait.php
index 21168282..eaa34dc0 100644
--- a/src/Entity/Base/MasterAttachmentTrait.php
+++ b/src/Entity/Base/MasterAttachmentTrait.php
@@ -33,10 +33,10 @@ trait MasterAttachmentTrait
 {
     /**
      * @var Attachment|null
+     * Mapping is done in the subclasses (e.g. Part), like with the attachments.
+     * If this is done here (which is possible in theory), the attachment is not lazy loaded anymore, which causes unnecessary overhead.
      */
     #[Assert\Expression('value == null or value.isPicture()', message: 'part.master_attachment.must_be_picture')]
-    #[ORM\ManyToOne(targetEntity: Attachment::class)]
-    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
     protected ?Attachment $master_picture_attachment = null;
 
     /**
diff --git a/src/Entity/LabelSystem/LabelProfile.php b/src/Entity/LabelSystem/LabelProfile.php
index 30429985..c729b661 100644
--- a/src/Entity/LabelSystem/LabelProfile.php
+++ b/src/Entity/LabelSystem/LabelProfile.php
@@ -41,6 +41,8 @@ declare(strict_types=1);
 
 namespace App\Entity\LabelSystem;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\LabelProfileRepository;
 use App\EntityListeners\TreeCacheInvalidationListener;
 use Doctrine\DBAL\Types\Types;
@@ -68,6 +70,10 @@ class LabelProfile extends AttachmentContainingDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: AttachmentTypeAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /**
      * @var LabelOptions
      */
diff --git a/src/Entity/Parts/Category.php b/src/Entity/Parts/Category.php
index e5e3320e..23dd345c 100644
--- a/src/Entity/Parts/Category.php
+++ b/src/Entity/Parts/Category.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\CategoryRepository;
 use Doctrine\DBAL\Types\Types;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -118,6 +120,10 @@ class Category extends AbstractPartsContainingDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: CategoryAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, CategoryParameter>
      */
     #[Assert\Valid]
diff --git a/src/Entity/Parts/Footprint.php b/src/Entity/Parts/Footprint.php
index 8138f967..ccd5bd9f 100644
--- a/src/Entity/Parts/Footprint.php
+++ b/src/Entity/Parts/Footprint.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\FootprintRepository;
 use App\Entity\Base\AbstractStructuralDBElement;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -59,6 +61,10 @@ class Footprint extends AbstractPartsContainingDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: FootprintAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /**
      * @var FootprintAttachment|null
      */
diff --git a/src/Entity/Parts/Manufacturer.php b/src/Entity/Parts/Manufacturer.php
index b6768e4a..373ee950 100644
--- a/src/Entity/Parts/Manufacturer.php
+++ b/src/Entity/Parts/Manufacturer.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\ManufacturerRepository;
 use App\Entity\Base\AbstractStructuralDBElement;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -59,6 +61,10 @@ class Manufacturer extends AbstractCompany
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: ManufacturerAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, ManufacturerParameter>
      */
     #[Assert\Valid]
diff --git a/src/Entity/Parts/MeasurementUnit.php b/src/Entity/Parts/MeasurementUnit.php
index 054056a8..ebb7b0d0 100644
--- a/src/Entity/Parts/MeasurementUnit.php
+++ b/src/Entity/Parts/MeasurementUnit.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\MeasurementUnitRepository;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Base\AbstractStructuralDBElement;
@@ -90,6 +92,10 @@ class MeasurementUnit extends AbstractPartsContainingDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: MeasurementUnitAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, MeasurementUnitParameter>
      */
     #[Assert\Valid]
diff --git a/src/Entity/Parts/Part.php b/src/Entity/Parts/Part.php
index 2826e5fe..e425e145 100644
--- a/src/Entity/Parts/Part.php
+++ b/src/Entity/Parts/Part.php
@@ -22,6 +22,7 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\PartRepository;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Attachments\Attachment;
@@ -102,7 +103,7 @@ class Part extends AttachmentContainingDBElement
      * @var Attachment|null
      */
     #[Assert\Expression('value == null or value.isPicture()', message: 'part.master_attachment.must_be_picture')]
-    #[ORM\ManyToOne(targetEntity: Attachment::class)]
+    #[ORM\ManyToOne(targetEntity: PartAttachment::class)]
     #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
     protected ?Attachment $master_picture_attachment = null;
 
diff --git a/src/Entity/Parts/Storelocation.php b/src/Entity/Parts/Storelocation.php
index 08c4911b..a519f6c1 100644
--- a/src/Entity/Parts/Storelocation.php
+++ b/src/Entity/Parts/Storelocation.php
@@ -22,6 +22,7 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
 use App\Repository\Parts\StorelocationRepository;
 use Doctrine\DBAL\Types\Types;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -109,6 +110,10 @@ class Storelocation extends AbstractPartsContainingDBElement
     #[ORM\OneToMany(targetEntity: StorelocationAttachment::class, mappedBy: 'element', cascade: ['persist', 'remove'], orphanRemoval: true)]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: StorelocationAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /********************************************************************************
      *
      *   Getters
diff --git a/src/Entity/Parts/Supplier.php b/src/Entity/Parts/Supplier.php
index 34483ca3..b50bcd45 100644
--- a/src/Entity/Parts/Supplier.php
+++ b/src/Entity/Parts/Supplier.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\Parts;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\SupplierRepository;
 use App\Entity\PriceInformations\Orderdetail;
 use Doctrine\Common\Collections\ArrayCollection;
@@ -91,6 +93,10 @@ class Supplier extends AbstractCompany
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: SupplierAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, SupplierParameter>
      */
     #[Assert\Valid]
diff --git a/src/Entity/PriceInformations/Currency.php b/src/Entity/PriceInformations/Currency.php
index 548e45f6..6ad526a7 100644
--- a/src/Entity/PriceInformations/Currency.php
+++ b/src/Entity/PriceInformations/Currency.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\PriceInformations;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\CurrencyRepository;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Attachments\CurrencyAttachment;
@@ -84,6 +86,10 @@ class Currency extends AbstractStructuralDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: CurrencyAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, CurrencyParameter>
      */
     #[Assert\Valid]
diff --git a/src/Entity/ProjectSystem/Project.php b/src/Entity/ProjectSystem/Project.php
index f202beaa..fd6ac8ba 100644
--- a/src/Entity/ProjectSystem/Project.php
+++ b/src/Entity/ProjectSystem/Project.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\ProjectSystem;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\Parts\DeviceRepository;
 use App\Validator\Constraints\UniqueObjectCollection;
 use Doctrine\DBAL\Types\Types;
@@ -93,6 +95,10 @@ class Project extends AbstractStructuralDBElement
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: ProjectAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var Collection<int, ProjectParameter>
      */
     #[ORM\OneToMany(targetEntity: ProjectParameter::class, mappedBy: 'element', cascade: ['persist', 'remove'], orphanRemoval: true)]
diff --git a/src/Entity/UserSystem/Group.php b/src/Entity/UserSystem/Group.php
index b56cabf4..31c9c26a 100644
--- a/src/Entity/UserSystem/Group.php
+++ b/src/Entity/UserSystem/Group.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\UserSystem;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Validator\Constraints\NoLockout;
 use Doctrine\DBAL\Types\Types;
 use App\Entity\Attachments\GroupAttachment;
@@ -76,6 +78,10 @@ class Group extends AbstractStructuralDBElement implements HasPermissionsInterfa
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: GroupAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     #[Groups(['full'])]
     #[ORM\Embedded(class: PermissionData::class, columnPrefix: 'permissions_')]
     #[ValidPermission()]
diff --git a/src/Entity/UserSystem/User.php b/src/Entity/UserSystem/User.php
index 9abf7070..70121bf4 100644
--- a/src/Entity/UserSystem/User.php
+++ b/src/Entity/UserSystem/User.php
@@ -22,6 +22,8 @@ declare(strict_types=1);
 
 namespace App\Entity\UserSystem;
 
+use App\Entity\Attachments\Attachment;
+use App\Entity\Attachments\AttachmentTypeAttachment;
 use App\Repository\UserRepository;
 use App\EntityListeners\TreeCacheInvalidationListener;
 use App\Validator\Constraints\NoLockout;
@@ -226,6 +228,10 @@ class User extends AttachmentContainingDBElement implements UserInterface, HasPe
     #[ORM\OrderBy(['name' => 'ASC'])]
     protected Collection $attachments;
 
+    #[ORM\OneToOne(targetEntity: UserAttachment::class)]
+    #[ORM\JoinColumn(name: 'id_preview_attachment', onDelete: 'SET NULL')]
+    protected ?Attachment $master_picture_attachment = null;
+
     /** @var \DateTimeInterface|null The time when the backup codes were generated
      */
     #[Groups(['full'])]