get-term-being-edited.php

<?php

/**
 * Get the term currently being edited on the edit.php screen
 * in the WordPress admin.
 *
 * @return WP_Term|null The term object or null on failure.
 */
function km_get_term_being_edited() {
	global $taxnow;

	if ( ! $taxnow || empty( $_GET['tag_ID'] ) ) {
		return null;
	}

	$term_id = absint( $_GET['tag_ID'] );
	$term    = get_term( $term_id, $taxnow );

	return $term instanceof WP_Term ? $term : null;
}