When a user is enrolled in many courses and creating a new course Calendar Event, the course dropdown list does not display all courses naturally. If the user then tries to use the scroll bar or keyboard navigation, the course list immediately collapses and resets the dropdown list so that the other courses cannot be viewed.

1. Enroll an instructor in ~10+ courses
2. Go to the Site Calendar view : /calendar/view.php?view=month
3. Create a New Event
4. Select Course Event and view the course dropdown list.

Observed Result: The course list does not show in full naturally and could be more accessible. If you attempt to use the keyboard or just a mouse click on the scroll bar, the course list pop-up closes immediately.

Expected Result: The course list can be viewed in full by using the scrollbar or keyboard navigation.

Workaround: Using either a mouse wheel or selecting 'Show More' to expand the Calendar Event options page then allows for the entire course list to be viewed with the scrollbar. However, this is not easily accessible for users relying on their keyboard who do not use a scroll wheel or scrolling function.