By default, Drupal's Link URL field box in CKEditor 5 is just a textbox. it does not provide any clear guidance on how to link to internal vs external URLs, and does not provide any autocomplete functionality for internal links. The behavior of the links is also not easily configurable.
The linkit → module will provide autocomplete functionality and more. Some of this functionality will soon be in Drupal core, but the linkit module might still be useful, as it provides additional tools, like the ability to configure attributes on the links.
It will be worth considering whether linkit will be desirable even after the primary fixes are brought into Drupal core.
Active
2.0
Code
My mistake. Linkit is already present in Drutopia.
Though it is present, I decided to keep open, since this should probably be configured upon installation. Renaming accoringly.