Drupal 8 Link field template

field--paragraph--field-link--button.html.twig

{#
/**
 * @file
 * Template for field_link on a Button Paragraph.
 */
#}
{% for item in items %}

  {% set classes = ['btn'] %}
  {% set button_style = element['#object'].field_button_style.value|default('primary') %}

  {% if button_style == 'primary' %}
    {% set classes = classes|merge(['btn-primary']) %}
  {% elseif button_style == 'secondary' %}
    {% set classes = classes|merge(['btn-outline-primary']) %}
  {% endif %}

  {# Create attributes object, retaining UI/programatically added attributes.#}
  {% if item.content['#options'].attributes %}
    {% set link_attributes = create_attribute(item.content['#options'].attributes) %}
  {% else %}
    {% set link_attributes = create_attribute() %}
  {% endif %}

  <a{{ link_attributes.addClass(classes) }} href="{{ item.content['#url'].toString }}">{{- item.content['#title'] -}}</a>

{% endfor %}