If the user quickly clicks on the search box while some stuff is still loading/running, the "normal" search suggestions box (that is, the suggestions box that appears on other wikis) will appear over the special Wikidata search suggestions box as the user is typing. In most situations, the box will have just the "containing..." bit, unless the user inputs "Q" or some such. The Wikidata suggestions box has a z-index of 1, lower than the normal box which has a z-index of 1099, so the top suggestions are covered.
This makes the first and most important search result inaccessible.
Workaround: ...