Deleted or Unexisting groups can't be removed from Global Permissions

Summary

After deleting a group from the Site Administration, the group keeps showing up on the Global Permissions page with a group not found message - it also happens when we migrate data from server to cloud products, in case the group do not exist in the cloud environment.
 

Steps to Reproduce

1. Go to a site administration and delete a group
2. Go to Global Permissions page and remove all permissions for the Deleted group.

Expected Results

The deleted group should disappear from the Global Permissions page.

Actual Results

The deleted group keeps showing on the Global Permissions page with a group not found message.

Workaround

Raise a support ticket in our customer portal, mentioning this bug request. Our team will talk to you and get the deleted groups removed from the Global Permissions session.