It's the thing you do to apply for the visa. You may worry that, because there is no language in this section specifying which visas this travel restriction applies to (newly issued/renewed, etc), and because of the inclusion of the word "supplemented," that this travel restriction applies broadly to all issued H1-B visas. And, well, the immigration lawyers at Microsoft[1] seem to share that worry.

[1] https://economictimes.indiatimes.com/nri/work/microsoft-urge...