How do I use hook_preprocess_page_title() on a Bootstrap subtheme?
How do I add hook_preprocess_page_title() in a Bootstrap theme?


In your sub-theme's .theme file you add:

/*
 * Implements hook_preprocess_page_title()
 */
SUB_THEME_NAME_preprocess_page_title(&amp;$variables) {
  // your logic goes here
}