Script UI question

In my panel I have a drop-down list, from which I can select an item. Below that UI element there are buttons which are enabled at the time I can select from the list:

The list reacts on OnChanage. The buttons of course on OnClick.

If I 'accidentally' select by double click (only the 3rd and 4th list element are relevant for this) then the buttons underneath the cursor location also react (currently with a message "not implemented").

How can I avoid this?

Disabling the two buttons in the OnChange call back function of the drop-down list does not help, because in the further processing of the selection the buttons are enabled. And my computer seems to be faster than my double click interval...

I think I must consume the double click in a call back function for the list. But there is no onDoubleClick event type for drop-down lists.

Documenting this behaviour might be the only means.