Deprecated errors str_replace Passing null to parameter

Hi there, thanks for this plugin!

Query Monitor gives me two Deprecated errors:

strpos(): Passing null to parameter #1 ($haystack) of type string is deprecated

wp-includes/functions.php:7022
strpos()
wp-includes/functions.php:7022
wp_is_stream()
wp-includes/functions.php:2155
wp_normalize_path()
wp-includes/plugin.php:768
plugin_basename()
wp-admin/includes/plugin.php:1405
add_submenu_page()
wp-content/plugins/mollie-forms/classes/Admin.php:82
MollieForms\Admin->adminMenu()
wp-includes/class-wp-hook.php:308
do_action('admin_menu')
wp-admin/includes/menu.php:155

and

Deprecated str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated

wp-includes/functions.php:2162
str_replace()
wp-includes/functions.php:2162
wp_normalize_path()
wp-includes/plugin.php:768
plugin_basename()
wp-admin/includes/plugin.php:1405
add_submenu_page()
wp-content/plugins/mollie-forms/classes/Admin.php:82
MollieForms\Admin->adminMenu()
wp-includes/class-wp-hook.php:308
do_action('admin_menu')
wp-admin/includes/menu.php:155

Perhaps you mind taking a look? Thanks in advance!