FR: customize this behavior of ComboBox

When the menu for a combo is so tall that it doesn’t fit neither under nor above the combo box, some of its items appear right beneath the mouse cursor.
If the mouse button is kept down for “long enough”, that item gets selected as soon as the button is released.

This behavior is there to allow this behavior: if I open any combo menu and I hold the mouse button down, I can move the cursor over any item in the menu and that item gets selected when I release the mouse button.

Turns out that the “time treshold” for that is hardcoded to be 250ms and it cannot be nor changed, nor it is possible to completely disable the second behaviour (which in the end it’s what I’d like to do by setting a time treshold very high)

Is it possible to add a popup menu option to customize that?