Steps to reproduce the issue

Create a fields plugin. extend an existing field (I was extending checkbox) within a fields folder of my new custom field. In the plugin php - use $form->addFieldPath(JPATH_PLUGINS.'/fields/yourfield/fields'); to allow the plugin to use your new field.

In /administrator - I can edit a user after creating a custom field and that field displays as expected. When I edit the profile as a user - I'm given a text field (the fallback)

This is confusing to write.... I hope I'm explaining it well enough.

Expected result

addFieldPath functions in both front-end and backend

Actual result

addFieldPath only functions in backend

System information (as much as possible)

PHP7.1.11, Nginx, MariaDB10.2.11

Additional comments