I'm upgrading the Drupal 6 project to Drupal 8 using drupal migrate UI module.
I've installed the below modules in Drupal 8 for an upgrade from 6 to 8.
- Nice Menus
- Views Slideshow
But, those are not showing in "MODULES WILL BE UPGRADED" list.
What needs to be done before proceeding for "Perform Upgrade". Thanks in advance.