How long should a toast message with 'undo' appear?

Yeah, the undo is available to recover from specific recent actions. To clarify, the alter remains visible for 60 seconds, then fades away OR may be dismissed. If the user hovers over the alert, the countdown is reset to 60 seconds again.

1. How long should a toast message last?
2. Can a toast have an undo button?
3. How long should a toast display?
4. Where should toast message appear?

How long should a toast message last?

Issue #1: How long should toasts stay up for? A good length of time to keep messages up is 5 seconds plus 1 extra second for every 120 words, rounding up. This is how fast the average American reads. That means the shortest default that should be used as a best practice is 6 seconds.

Can a toast have an undo button?

If you change your mind when deleting a record, you can undo the deletion without going to the Recycle Bin.

How long should a toast display?

Also, toasts will typically display for 2-5 seconds. A time frame of 3 seconds is ideal for most users. However, you can adjust the toast's exit timing to make it disappear quicker, so users don't have to wait.

Where should toast message appear?

Toast messages ensure that the use of the application is not interrupted while providing necessary information for the user. They have no notification sounds associated with them and don't appear in the notification centers on any platform, but appear at the bottom of the viewport by default.