UIEffect | effect component for uGUI element | User Interface library

My goal was to make a combo box which shows the down arrow only when the mouse is hovering above it. To do that I subclassed QComboBox and reimplemented enterEvent and leaveEvent which would change its stylesheet accordingly. It works just as expected, when to window shows up, down arrow is hidden and when the mouse hovers above combo box, the down arrow shows up. Then, when the mouse clicks on combo box text, the drop down list shows up and the down arrow becomes invisible again (which I can deal with, but if someone has a solution I'm all ears). The main problem is when the mouse clicks on the drop down arrow, instead of just hiding the drop down arrow, as it did when mouse clicked on the text, it also hides the text along with the drop down arrow. I did some testing to find out what's causing the problem and it seems that calling setEffectEnabled(Qt.UIEffect.UI_AnimateCombo, False) on QApplication is the issue, although I have no idea how disabling drop down animation is related to making text disappear when clicking on drop down arrow. Also, if someone has more elegant way of doing what I want, again, I'm all ears :). Here's the example code: