Unable to select multiple values in drop-down menu while mapping site-wide feedback to courses

After creating a feedback activity on the site front page and attempting to map the feedback to courses, if the search result returns more than one course in the drop-down menu you are unable to select multiple courses - despite the tool-tip to the right indicating you should be able to.

Have noted that a possible cause is that the results drop down field seems to have been declared in the HTML as 'select' instead of 'select multiple'.

Have been able to reproduce this in 2.4, 2.5, and 2.7 (assuming this is likely also present in 2.6).

Steps to reproduce:

1. Create a feedback activity on the site front page
2. Inside the activity, click on the 'Map feedback to courses' button
3. In the course search field, enter a term that will return at least 2 results from your available courses
4. Take note of the help tip to the right of 'Map Feedback to courses' button that states 'Multiple courses may be selected by holding down the Apple or Ctrl key whilst clicking on the course names'
5. Attempt to select multiple courses from the search results drop-down menu