(PHP 8 >= 8.4.0)
Dom\TokenList::toggle — Toggles the presence of a token in the list
   Toggles the presence of token in the list.
  
Dom\SYNTAX_ERR if a token is the empty string.
  
 Dom\INVALID_CHARACTER_ERR if a token contains any
   ASCII whitespace.
  
 Example #1 Dom\TokenList::toggle() example
    Toggles three classes, two without force, and one with.
   
<?php
$dom = Dom\HTMLDocument::createFromString('<p class="font-bold important"></p>', LIBXML_NOERROR);
$p = $dom->body->firstChild;
$classList = $p->classList;
$classList->toggle('font-bold', 'font-small');
$classList->toggle('important', force: true);
echo $dom->saveHtml($p);
?>The above example will output:
<p class="font-bold important"></p>
