I’m unable to get a default placeholder and/or size to register against a BaseFieldDefinition. I’m trying something like:

$  fields['company_name'] = BaseFieldDefinition::create('string')       ->setLabel(t('Company Name'))       ->setDescription(t('What\'s your company called?'))       ->setDefaultValue('')       ->setDisplayOptions('form', [         'type' => 'string_textfield',         'settings' => [           'display_label' => TRUE,           'size' => 10,           'placeholder' => '',         ],         'weight' => '9',       ])       ->setDisplayConfigurable('form', TRUE); 

But when I enable my module, and check the ‘Manage Form Display’ tab for the relevant entity, it shows the defaults (size = 60, placeholder = {null}).

Does anyone know how to get these working..? Especially the placeholder one.