private function promo_message() {

		$this->translation_details();

		$message = false;

		if ( $this->translation_exists && $this->translation_loaded && $this->percent_translated < 90 ) {
			/* translators: 1: language name; 3: completion percentage; 4: link to translation platform. */
			$message = __( 'As you can see, there is a translation of this plugin in %1$s. This translation is currently %3$d%% complete. We need your help to make it complete and to fix any errors. Please register at %4$s to help complete the translation to %1$s!', $this->textdomain );
		}
		elseif ( ! $this->translation_loaded && $this->translation_exists ) {
			/* translators: 1: language name; 2: plugin name; 3: completion percentage; 4: link to translation platform. */
			$message = __( 'You\'re using WordPress in %1$s. While %2$s has been translated to %1$s for %3$d%%, it\'s not been shipped with the plugin yet. You can help! Register at %4$s to help complete the translation to %1$s!', $this->textdomain );
		}
		elseif ( ! $this->translation_exists ) {
			/* translators: 2: plugin name; 4: link to translation platform. */
			$message = __( 'You\'re using WordPress in a language we don\'t support yet. We\'d love for %2$s to be translated in that language too, but unfortunately, it isn\'t right now. You can change that! Register at %4$s to help translate it!', $this->textdomain );
		}

		$registration_link = sprintf(
			'<a href="%1$s">%2$s</a>',
			esc_url( $this->register_url ),
			esc_html( $this->glotpress_name )
		);

		$message = sprintf(
			esc_html( $message ),
			esc_html( $this->locale_name ),
			esc_html( $this->plugin_name ),
			(int) $this->percent_translated,
			$registration_link
		);

		if ( $message ) {
			$message = '<p>' . $message . '</p><p><a href="' . esc_url( $this->register_url ) . '">' . esc_html__( 'Register now &raquo;', $this->textdomain ) . '</a></p>';
		}

		return $message;
	}