I have newsletters, some do not belong to a group (they are universal) and some belong to groups. I want to be able to see both in the same view, depending on whether a filter is applied or not. How can I do this in Drupal 8?
This is similar to this question, which was created for Drupal 7. List your own content of groups and all non-group content on the group page
In Drupal 8, however, the group module is used instead of organic groups.