adaptivetheme-8.x-3.x-dev/at_core/forms/ext/extension_settings_skin.php

<?php

/**
 * @file
 * Generate form elements for the Extension settings for Skin type themes.
 */

$form['docs'] = [
  '#type' => 'container',
  '#markup' => t('<a class="at-docs" href=":docs" target="_blank" title="External link: docs.adaptivethemes.com">View online documentation <svg class="docs-ext-link-icon" viewBox="0 0 1792 1792" xmlns="http://www.w3.org/2000/svg"><path d="M1408 928v320q0 119-84.5 203.5t-203.5 84.5h-832q-119 0-203.5-84.5t-84.5-203.5v-832q0-119 84.5-203.5t203.5-84.5h704q14 0 23 9t9 23v64q0 14-9 23t-23 9h-704q-66 0-113 47t-47 113v832q0 66 47 113t113 47h832q66 0 113-47t47-113v-320q0-14 9-23t23-9h64q14 0 23 9t9 23zm384-864v512q0 26-19 45t-45 19-45-19l-176-176-652 652q-10 10-23 10t-23-10l-114-114q-10-10-10-23t10-23l652-652-176-176q-19-19-19-45t19-45 45-19h512q26 0 45 19t19 45z"/></svg></a>', [':docs' => ' //docs.adaptivethemes.com/']),
  '#weight' => -1000,
];

$form['message'] = [
  '#type' => 'container',
  '#prefix' => '<div class="message-skin">',
  '#suffix' => '</div>',
  '#markup' => t('<b>@themename</b> is a skin type theme (sub-sub theme) and will inherit extension and layout settings from it\'s base theme (@basetheme).', ['@themename' => $theme, '@basetheme' => $getThemeInfo['base theme']]),
  '#weight' => -1000,
];