SelectableUrlField
SelectableUrlField allows Users to insert the URL of a specific model by first chose a data-type, then an instance of that datatype. For example, a User might chose 'Page' and then 'About', which will save the url to the /about (the url returned when calling getUrl() on the Page instance with the slug of about).
To configure this field, you should add the crud_names of any Cruds that you want to be selectable with either addCrudName, addCrudNames or crudNames
e.g.
SelectableUrlField('content_link')
->crudNames([
'page',
'post',
'category',
]),