Popup menu of combobox does not disappear until i choose an item

I have a combobox to show preset list. In windows everything works fine. I click on comobox label, It displays the preset list in it’s popup menu. I can choose a preset or just click on somewhere else. if I click on somewhere else, popup menu disapears. And this is how it is supposed to be. But in Mac when i click on somewhere else, popup menu stays there. It does not disappears.I move the plugin window, it still stays there. I have to choose a item to make it disappear.Is there anyone else who came across to this issue?

Edit: It disappers, if i click on somewhere within plugin window but if i click on combobox, make it show the popup menu and then click on the frame of the plug in window and try to drag it, it does not disapper. Looks like it cannot notice that i clicked on the frame. The last focus stays on the popup menu of the combobox.