To eliminate the residual styling caused by Twenty Seventeen, we’ll do a simple manual integration.

1. Create a child theme

If you haven’t already, create a child theme. Make all your edits in the child theme so that they don’t get overwritten when you update Twenty Seventeen.

2. Copy your header.php into the child theme

Take Twenty Seventeen’s header.php and copy it into the child theme’s folder.

3. Manually integrate

In the child theme header.php, find the menu code:

Specifically, find this line:

<?php get_template_part( 'template-parts/navigation/navigation', 'top' ); ?>

We will replace it with UberMenu, conditionally:

<?php if( function_exists( 'ubermenu' ) ): ?>
	<?php ubermenu( 'main' , array( 'theme_location' => 'top' ) ); ?>
<?php else: ?>
	<?php get_template_part( 'template-parts/navigation/navigation', 'top' ); ?>
<?php endif; ?>

Now UberMenu is integrated and can be used without interference from the theme.