public function set_initial_quote_tags( $tags = [ 'p', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'blockquote', 'li', 'dd', 'dt' ] ) {
		// Make array if handed a list of tags as a string.
		if ( ! \is_array( $tags ) ) {
			$tags = \preg_split( '/[^a-z0-9]+/', $tags, -1, PREG_SPLIT_NO_EMPTY );
		}

		// Store the tag array inverted (with the tagName as its index for faster lookup).
		$this->data['initialQuoteTags'] = \array_change_key_case( \array_flip( /** Array. @scrutinizer ignore-type */ $tags ), CASE_LOWER );
	}