How to get menu title inside menu--main.html.twig file I created a suggestion for menu and using menu--main-sidebar.html to render menu. 

I want to include menu title (title of block added to specific region from admin side) as first child of menu

I tried to use configuration (configuration.label shows menu title in block--menu-block--main.html.twig file) like below

{{ menus.menu_links(items, attributes, menu_level, menu_name, configuration) }}


That does not work. 

So, how to get the menu title inside menu_links in menu--main.html.twig file?
You could try using the Simplify Menu module (which extends twig to support direct access to Drupal's menus for overriding markup).

See the example in this related thread: https://drupal.stackexchange.com/a/228982/79832