Should a toast library show only one toast at a time?

Ding keeps one toast on screen and morphs it when a new call comes in, so "Saving…" turns into "Saved" in place instead of stacking.

The tradeoff is you lose history. If two things finish close together, the second replaces the first.

For the apps you build, would you prefer a single toast like this, a stack, or something in between? Curious where this breaks for you.