How do I include composer.libraries.json in root composer.json without using the wikimedia/composer-merge-plugin plugin?
here is a specific way how to do it for webform module.

run composer require wikimedia/composer-merge-plugin
in composer add


  &quot;merge-plugin&quot;: {
            &quot;include&quot;: [
                &quot;web/modules/contrib/webform/composer.libraries.json&quot;
            ]
        },



run composer update --lock and verify the files

Reference https://www.drupal.org/docs/8/modules/webform/webform-frequently-asked-questions/how-to-use-composer-to-install-libraries
Reference 2 https://www.drupal.org/docs/8/modules/webform/webform-cookbook/using-the-composer-merge-plugin-to-download-libraries-with
Github issue https://github.com/wikimedia/composer-merge-plugin/issues/184