I3f6c916de28f0bf70d9e8a9b7d6f5735131954eb for T190156 optimized the way the first item in the match list is highlighted.
In doing so it also introduced an object state filterQuery that caches the previous run's input value. Highlighting for items is now only executed if the input value changed compared to the last run.
This causes problems when updateItemVisibility is repeatedly run (e.g. because of filterFromInput) or after asynchronous request (e.g. RequestManager mixin) - in subsequent runs this.items is not iterated over and anyVisible never reaches the true state leaving the widget and options in invisible state despite items that should be shown.