Issue #3322583: Undefined array key "type" in bootstrap5_preprocess_input()

Closes #3322583

src/Element/BootstrapDate.php

@@ -92,6 +92,9 @@ class BootstrapDate extends FormElement {
     // Load the Bootstrap datepicker title via data-provide attribute.
     $settings['data-date-title'] = $element['#datepicker_title'] ?? NULL;
 
+    // Set the attributes type which is used by themes.
+    $settings['type'] = 'bootstrap_datepicker';
+
     // Append our attributes to element.
     $element['#attributes'] += $settings;