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apply_filters( 'wp_unique_term_slug_is_bad_slug', bool $needs_suffix, string $slug, object $term )

Filters whether the proposed unique term slug is bad.

$needs_suffix: (bool) Whether the slug needs to be made unique with a suffix.
$slug: (string) The slug.
$term: (object) Term object.

Used By	Description
wp-includes/taxonomy.php: wp_unique_term_slug()	Will make slug unique, if it isn’t already.

Version	Description
4.3.0	Introduced.