By default at install time Webform adds a content type called Webform without a standard body field attached to it. To change this behaviour Webform 7.x used variables. In Webform 8.x the config system is used for the same functionality, with the same defaults.
This feature would typically be used only for install profiles or distributions who require control of what Webform creates at install time.
Webform 7.x
- In settings.php
$conf['webform_install_create_content_type'] = FALSE;or elsewherevariable_set('webform_install_create_content_type', FALSE); - In settings.php
$conf['webform_install_add_body_field'] = TRUE;or elsewherevariable_set('webform_install_add_body_field', TRUE);
Webform 8.x
$config['webform.settings']['install_skip_content_type_creation'] = TRUE;$config['webform.settings']['install_add_body_field'] = TRUE;
Setting these values before Webform install with the config system (e.g. \Drupal::configFactory()->getEditable('webform.settings')->set('install_skip_content_type_creation', TRUE)->save();) is not supported by Drupal which would then disallow module install with "Unable to install Webform, webform.settings already exists in active configuration."
Note the rename of 'webform_install_create_content_type' to 'install_skip_content_type_creation'.