Group menu link item translation issue

No more info about this ?
I would also need to be able to translate menu group links and i don't see any way of doing it at the moment

I bump into this.
I reproduced it on a clean install, so it may be a problem on either group_content_menu or something similar to core's 🐛 Error: Call to a member function label() on null in Drupal\menu_link_content\Form\MenuLinkContentForm->form() (line 99 of /var/www/html/docroot/core/modules/menu_link_content/src/Form/MenuLinkContentForm.php). Fixed .

Issue description filled with more details.

The problem describe on testing steps, and on the added failed test case, can be fixed with patch for core attached below.
Feedback about it is highly welcome.
Not entirely sure it is the right solution, since I have not looked at all possible cases for core.

I took a look at the core patch. I makes sense. Should we open an upstream issue?

I can translate the menu item of the group content when I translate the node itself.
But when I use the contextual link "Edit menu" and then try to translate a menu item, then I got (1) an error message, (2) a status message that the menu link has been edited, and (3) the menu item is deleted from the menu.

This is the case for menu items that link to nodes as well as to the group itself.

Deprecated function: explode(): Passing null to parameter #2 ($string) of type string is deprecated in Drupal\menu_link_content\Form\MenuLinkContentForm->buildEntity() (line 114 of core/modules/menu_link_content/src/Form/MenuLinkContentForm.php).

Drupal\menu_link_content\Form\MenuLinkContentForm->buildEntity(Array, Object) (Line: 186)
Drupal\Core\Entity\ContentEntityForm->validateForm(Array, Object)
call_user_func_array(Array, Array) (Line: 82)
Drupal\Core\Form\FormValidator->executeValidateHandlers(Array, Object) (Line: 275)
Drupal\Core\Form\FormValidator->doValidateForm(Array, Object, 'menu_link_content_menu_link_content_form') (Line: 118)
Drupal\Core\Form\FormValidator->validateForm('menu_link_content_menu_link_content_form', Array, Object) (Line: 593)
Drupal\Core\Form\FormBuilder->processForm('menu_link_content_menu_link_content_form', Array, Object) (Line: 325)
Drupal\Core\Form\FormBuilder->buildForm(Object, Object) (Line: 48)
Drupal\Core\Entity\EntityFormBuilder->getForm(Object, 'default', Array) (Line: 394)
Drupal\content_translation\Controller\ContentTranslationController->add(Object, Object, Object, 'menu_link_content')
call_user_func_array(Array, Array) (Line: 123)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 580)
Drupal\Core\Render\Renderer->executeInRenderContext(Object, Object) (Line: 124)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext(Array, Array) (Line: 97)
Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 169)
Symfony\Component\HttpKernel\HttpKernel->handleRaw(Object, 1) (Line: 81)
Symfony\Component\HttpKernel\HttpKernel->handle(Object, 1, 1) (Line: 58)
Drupal\Core\StackMiddleware\Session->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\KernelPreHandle->handle(Object, 1, 1) (Line: 106)
Drupal\page_cache\StackMiddleware\PageCache->pass(Object, 1, 1) (Line: 85)
Drupal\page_cache\StackMiddleware\PageCache->handle(Object, 1, 1) (Line: 48)
Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle(Object, 1, 1) (Line: 51)
Drupal\Core\StackMiddleware\NegotiationMiddleware->handle(Object, 1, 1) (Line: 23)
Stack\StackedHttpKernel->handle(Object, 1, 1) (Line: 718)
Drupal\Core\DrupalKernel->handle(Object) (Line: 19)

I am seeing an actual issue with the operational links at /group/16/menu/81/edit

Error:

Error: Call to a member function access() on null in Drupal\group_content_menu\Form\GroupContentMenuForm->buildOverviewTreeForm() (line 313 of modules/contrib/group_content_menu/src/Form/GroupContentMenuForm.php).

Drupal\group_content_menu\Form\GroupContentMenuForm->buildForm()
call_user_func_array() (Line: 536)
Drupal\Core\Form\FormBuilder->retrieveForm() (Line: 284)
Drupal\Core\Form\FormBuilder->buildForm() (Line: 73)

I don't think it was the original issue found here, but it is an issue with menu link translations.