UPDATE:
We fixed this issue but need some more testings and update before releasing new version for T4 framework.
At this moment, you can update this file:
/plugins/system/t4/themes/base/html/layouts/t4/element/megamenu-toggle.php
Here is updated code in the file:
<?php
$paramsTpl = JFactory::getApplication()->getTemplate(true)->params;
$navigation_settings = $paramsTpl->get('navigation-settings');
if (!filter_var($navigation_settings->get('mega_showsm'), FILTER_VALIDATE_BOOLEAN)) return;
$menuType = $navigation_settings->get('menu_type', 'mainmenu');
$navid = 't4-megamenu-' . $menuType;
?>
<nav class="navbar-expand-<?php echo $navigation_settings->get('option_breakpoint', 'lg')?>">
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#<?php echo $navid ?>" data-bs-toggle="collapse" data-bs-target="#<?php echo $navid ?>" aria-expanded="false" aria-label="Toggle navigation">
<i class="fa fa-bars toggle-bars"></i>
</button>
</nav>
Pls note that if you already overrode this megamenu element in template on your site, you need to edit that override file instead of above core file:
/templates/t4_bs5_blank/html/layouts/t4/element/megamenu-toggle.php
/templates/t4_bs5_blank/local/html/layouts/t4/element/megamenu-toggle.php
Let me know if this helps 🙂
