Customize VisibleFields CSS on a Many-To-Many Object Relations field

Hello =)

I’m trying to customize CSS visible fields on my Many-To-Many Object Relations (I want to have a specific CSS for my Visible Fields (force a width)

My definition_object.php is :

Pimcore\Model\DataObject\ClassDefinition\Data\ManyToManyObjectRelation::__set_state(array(
             'fieldtype' => 'manyToManyObjectRelation',
             'width' => '',
             'height' => '',
             'maxItems' => '',
             'queryColumnType' => 'text',
             'phpdocType' => 'array',
             'relationType' => true,
             'visibleFields' => 'ImageDefault,MASTER_ID,REF_MARQUE,MASTER_NAME',
             'allowToCreateNewObject' => true,
             'optimizedAdminLoading' => false,
             'visibleFieldDefinitions' => 
            array (
            ),
             'classes' => 

Maybe I can set CSS data in VisibleFieldDefinitions part ? (for example, I would like to force my ‘ImageDefault’ visible field with a width of 200px)

Current Behavior :

Expected Behavior :

Thanks in advance for your precious help

Benjamin

Field-specific CSS can be set in the backend of PIM by writing the CSS under field’s attribute as given below:
image