Call to a member function render() on string

Problem/Motivation

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Error: Call to a member function render() on string in Drupal\custom_formatters\Plugin\CustomFormatters\FormatterType\FormatterPreset->settingsForm() (line 79 of modules/contrib/custom_formatters/src/Plugin/CustomFormatters/FormatterType/FormatterPreset.php).

Steps to reproduce

// Get Formatter type settings form.
$plugin_form = [];
$form['plugin'] = $formatter_type->settingsForm($plugin_form, $form_state);

Errors is thrown here:
modules/contrib/custom_formatters/src/Plugin/CustomFormatters/FormatterType/FormatterPreset.php:79
// Build formatters list.
$options = [];
$formatters = $this->formatterManager->getDefinitions();
foreach ($formatters as $formatter_name => $formatter) {
if (in_array($field_type, $formatter['field_types'])) {
/** @var \Drupal\Core\StringTranslation\TranslatableMarkup $label */
$label = $formatter['label'];
$options[$formatter_name] = $label->render();
}
}

Proposed resolution

$label is string, so can't $label->render();

Remaining tasks

User interface changes

API changes

Data model changes