No @jobara, at least on my side, there is no focus listener registered. The only place i see hooks for focus event is at the combobox created by Alex, 
https://github.com/chrispetsos/prefsEditors/blob/master/src/shared/adjusters/js/combobox.js#L39-L41
https://github.com/chrispetsos/prefsEditors/blob/master/src/shared/adjusters/js/combobox.js#L82-L84
used in the language selection adjusters.