This works by design. The difference between those items is that you can actually click New without invoking the submenu, and it will create a new (empty) tab. The same for the Execute item: you can display a submenu (by clicking the arraw), or you can just click it to perform the default action (e.g. execute the entire script). This is similar to some buttons on MS Word’s toolbars (e.g. Highlight). So, I would not be so eager to raise a CR on this. And it’s definitely not a bug.
PS. BTW you can change your UI style in Preferences, say, to XP or Office and will see that those items (New, Execute and several others) even look slightly different to others, and the dropdown arrow isn’t highlighted when you select such item.
Message was edited by: roman