What should someone on a Thai dependency visa do before traveling to Vietnam for a week?

A person on a Thai dependency visa planning to travel to Vietnam for a week should check the current visa regulations regarding re-entry to Thailand after their trip. They need to ensure their visa is valid and inquire if there's a need for any documentation or re-application upon returning. It's also advised to consult with immigration authorities to avoid any risk of losing their visa status after being outside Thailand for an extended period.