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<?php
 /**
 * Implements hook_page_init().
 *
 * @param Environment $env
 *   The Environment.
 * @param array $vars
 *   An array of variables.
 */
 function wysiwyg_page_init($env, $vars) {
 /** @var Page $page */
 $page = $vars['page'];
 
 if (Shadow::isOpen($env)) {
 // Include the codemirror lib.
 $page->addCSS('https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.3.0/codemirror.min.css');
 }
 }
 
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