The "group" entity type does not exist

Problem/Motivation

Adding data-entity-type="group" to an ul of links breaks the site.

Steps to reproduce

We have a View Attachment that has 4 fields it displays. One of these fields is a WYSIWYG field where one can add text and links. The links are added via linkit. For most pieces of content we have one or two links, among the other pieces of text. But for one node we have a text and some links where the links are in an <ul>.

It looks like linkit is adding data-entity-type="group" to each of the links inside the ul. This causes the white screen, and in the logs there's

Drupal\Component\Plugin\Exception\PluginNotFoundException: The "group" entity type does not exist

If we edit the node in question and remove the data-entity-type="group" for each of the links everything works as it should.