$form_data
$form_data : bool
Class Admin_Forms_Settings
$form_data : bool
render_api_key(array $field_data) : bool|string
Render API key field.
A masked/secret field with a show/hide toggle. The real value is stored in a hidden input
(submitted as um_options[<id>], exactly like a text field); a single visible, read-only
display input shows either the partially-masked value (first/last characters kept, middle
bulleted) or, once the eye button is toggled, the full editable value. Because only one
input is ever visible, the field can never look duplicated even if the stylesheet is stale.
Extra field config keys: reveal_prefix (int, default 6), reveal_suffix (int, default 4).
| array | $field_data |