diff --git a/app/components/work_package_relations_tab/add_work_package_child_dialog_component.html.erb b/app/components/work_package_relations_tab/add_work_package_child_dialog_component.html.erb
index d068472fdcff..1aedf05ea037 100644
--- a/app/components/work_package_relations_tab/add_work_package_child_dialog_component.html.erb
+++ b/app/components/work_package_relations_tab/add_work_package_child_dialog_component.html.erb
@@ -3,7 +3,7 @@
                                    size: :large,
                                    id: DIALOG_ID)) do |d|
     d.with_header(variant: :large)
-    d.with_body(classes: "Overlay-body_autocomplete_height") do
+    d.with_body(classes: body_classes) do
       render(WorkPackageRelationsTab::AddWorkPackageChildFormComponent.new(
         work_package: @work_package
       ))
diff --git a/app/components/work_package_relations_tab/add_work_package_child_dialog_component.rb b/app/components/work_package_relations_tab/add_work_package_child_dialog_component.rb
index 8f3ae85e92d2..fc7e09dee8df 100644
--- a/app/components/work_package_relations_tab/add_work_package_child_dialog_component.rb
+++ b/app/components/work_package_relations_tab/add_work_package_child_dialog_component.rb
@@ -51,4 +51,8 @@ def dialog_title
     child_label = t("#{I18N_NAMESPACE}.relations.label_child_singular")
     t("#{I18N_NAMESPACE}.label_add_x", x: child_label)
   end
+
+  def body_classes
+    "Overlay-body_autocomplete_height"
+  end
 end
diff --git a/app/components/work_package_relations_tab/work_package_relation_dialog_component.html.erb b/app/components/work_package_relations_tab/work_package_relation_dialog_component.html.erb
index d9cf73a50d36..2a804ff50d0b 100644
--- a/app/components/work_package_relations_tab/work_package_relation_dialog_component.html.erb
+++ b/app/components/work_package_relations_tab/work_package_relation_dialog_component.html.erb
@@ -3,7 +3,7 @@
                                    size: :large,
                                    id: DIALOG_ID)) do |d|
     d.with_header(variant: :large)
-    d.with_body(classes: "Overlay-body_autocomplete_height") do
+    d.with_body(classes: body_classes) do
       render(WorkPackageRelationsTab::WorkPackageRelationFormComponent.new(
         work_package: @work_package,
         relation: @relation
diff --git a/app/components/work_package_relations_tab/work_package_relation_dialog_component.rb b/app/components/work_package_relations_tab/work_package_relation_dialog_component.rb
index c56edcd2ba98..02fd5f33dd76 100644
--- a/app/components/work_package_relations_tab/work_package_relation_dialog_component.rb
+++ b/app/components/work_package_relations_tab/work_package_relation_dialog_component.rb
@@ -58,4 +58,8 @@ def dialog_title
       t("#{I18N_NAMESPACE}.label_add_x", x: relation_label)
     end
   end
+
+  def body_classes
+    @relation.persisted? ? nil : "Overlay-body_autocomplete_height"
+  end
 end