Toast dismal doesn't animate properly when dismissing the oldest toast

[jasoncavanaugh]

Toast: wrong toast animates on dismiss, remaining toasts snap upward

Environment

• Package version(s): @blueprintjs/core ^5.x
• Operating System: Mac Sonoma
• Browser name and version: Chrome 147.0.7727.138

Code Sandbox

Steps to reproduce

1. Navigate to https://blueprintjs.com/docs/#core/components/toast
2. Create more than one toast
3. Dismiss any toast that is not the most recent one to appear

Actual behavior

1. Notice that for a brief moment, the toast that appears to be dismissed is the most recent toast, before it corrects itself
2. Remaining toasts snap upward without any animation.

Expected behavior

The correct toast fades out and its occupied space collapses smoothly over the animation duration, so remaining toasts flow upward continuously with no snap.

Possible solution