Closing Sweet Alert modal (Alerts.alert) sometimes throws error

[spencern]

Expected behavior

Not to have client errors when closing Alert boxes.

Actual Behavior

When using a SweetAlert2 modal, closing it sometimes throws an error.
If closing by clicking on the 'overlay' the error looks like
Uncaught (in promise) overlay

If closing by timing out (use of timer setting such as timer: 2500):
Uncaught (in promise) timer

Steps to Reproduce the Behavior

Create an Alert with settings similar to the following

Alerts.alert({
                title: "Nice!",
                text: "Testing!",
                type: "success",
                timer: 2500,
                showCancelButton: true,
              }, function () {
                console.log("confirmed!");
              });

Click outside of the alert card to dismiss it or allow the timer to dismiss the alert and you should see an error in the console.

This appears to be a known issue
sweetalert2/sweetalert2#177

PR on the way.