A toast is a short, non-blocking notification. Like tooltips, toasts are opt-in: create a bootstrap.Toast and call show(). By default a toast hides itself after 5000 ms; set data-bs-autohide="false" or the { autohide: false } option to keep it, and then always include a close button. A toast holds an optional .toast-header and a .toast-body; .text-bg-* classes color the whole toast. Wrap toasts in a .toast-container, which stacks them with even spacing, and place it with position utilities (.position-fixed .bottom-0 .end-0). Alert renders two toasts beside alerts.
Use role="status" aria-live="polite" for routine news and role="alert" aria-live="assertive" only for errors, so screen readers do not interrupt the user for every "saved" message.