How to process html in twig file
Edited Code -

{% set build = {
      '#type':   'processed_text',
      '#text':    content.field_front_page_description.value,
      '#format': 'full_html',
} %}
      {{ kint(build) }}
      {{ build }}


Or,

{% set build = {
      '#type':   'processed_text',
      '#text':    node.field_front_page_description.value,
      '#format': 'full_html',
} %}
      {{ kint(build) }}
      {{ build }}