Demos - Selecting option does not dismiss list of options

On all the demos, when I select an option, the entire list continues to display. Use this as an example:

I expect only the selected option to display.

I tried clicking off the menu list, tapping the Escape key, tabbing off the control, none of which worked.

There are no errors in the console in the browser’s Web Developer Tools.

I tested across Firefox, Chrome, Safari, Opera on macOS, and on Chrome on Android.

This does appear to be a bug in the release version of Select2 v4.0.6. I’ve been using v4.0.6-rc.0 (Release Candidate 0), and it was working fine. So something broke. I hope the author of Select2 will see this post and fix the bug (whatever it is).