How can I use month name as contextual filter? I have a contextual filter to filter by month:

Date in the form of MM (01 - 12).

However, I want to filter by month name (january, february, march, etc.) to get nicer URL and breadcrumb.

Is there an easy way to do it?
You can programmatically alter the contextual filter value of "january" to "01 - 12" in hook_views_pre_view

/*
 * Implements hook_views_pre_view()
 */
function mymodule_views_pre_view(ViewExecutable $view, $display_id, array &amp;$args) {
  // Modify contextual filters for my_special_view.
  if ($view-&gt;id() == 'my_special_view') {
    // insert here some php magic to format "January" to "01".
    $og_arg = t('@og_arg', ['@og_arg' =&gt; $args[0]], ['langcode' =&gt; 'en']);
    $date = date_parse($og_arg);
    // assign formatted value.
    $args[0] = $date['month'];
  }
}