Since #2396145: Option #description_display for form element fieldset is not changing anything → the following exception appears when rendering a field group as a fieldset:
Warning: Undefined array key "#description_display" in template_preprocess_fieldset() (line 219 of core/includes/form.inc).
* Install Drupal 9.3 and Field Group
* Configure a view mode to display some fields in a fieldset
* Create and view an applicable entity
Determine if this module is generating fieldsets correctly, or if this is a core bug.
Closed: outdated
3.0
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