Issues assigned to wrong epic if epic is selected from 'Suggested' list

When creating an issue, if I select the epic link from the drop-down list of 'Suggested' options without typing anything in the box, it always appears to set the epic to the one below the epic I selected.

However, if I type the first few characters of the epic and then select it from the list, the epic link is set correctly.

I can reproduce this easily on both Firefox and Chrome so it doesn't appear to be a browser issue.