Focus remains on (hidden) modal element after close.

[duhrer]

In testing with Weavly, I can consistently get into a state where the optional focus indicator remains in the position of the last focused element within the modal, even after the modal closes.

I notice that the the last focused element does not receive focus either. So we have two problems:

1. There always needs to be a blur to clear the focus indicator in the modal, whether or not anything is focused in the rest of the page.
2. Whenever possible, focus should be restored when closing a modal.

The current steps I'm using to reproduce this are:

1. Open Weavly.
2. Create a program with a loop iterator and steps inside the loop.
3. Edit the number of iterations with the number helper.
4. Save the updated value using the "Update Field" button.
5. Hilarity ensues.