# Step 1
In this files:
resources/views/vendor/adminlte/partials/navbar/menu-item.blade.php
resources/views/vendor/adminlte/partials/sidebar/menu-item.blade.php
Change 
@inject('menuItemHelper', \JeroenNoten\LaravelAdminLte\Helpers\MenuItemHelper)
To
@inject('menuItemHelper', 'JeroenNoten\LaravelAdminLte\Helpers\NavbarItemHelper')


# Step 2
Change the method 'isSearchBar' to 'isSearch'