<button popovertarget="a" popovertargetaction="show">
  Show a toast
</button>
<button popovertarget="b" popovertargetaction="show">
  Show a toast
</button>
<div id="a" popover="auto" role="status">…</div>
<div id="b" popover="auto" role="status">…</div>

.toast:popover-open {
  animation: toast-life 5s forwards;
}