From the navigation template, let's take the Help tab; which dropdown is a list inside the div, as seen here: (with the list highlighted)
Now, there is a class that hides it by default, unless hovered over. This is basically handled with Popup, PopupControl, and PopupSelected in the parent list. So removing those will keep the links from showing, but when the tab is clicked, they are still there, as their default is still to show.
The css of course changes a bit, you might want to add a custom class there to set the color to show like the other tabs.
Here's where you find the three classes:
Removed the highlight (and save):
And the tab will show like this:
And when clicked the highlighted tab is still there, as are the child-list links:
Yep, i agree. Glad to see you fixed it. Since that works, that would have my preference as well.
Part of my post's intention was just to show you how I usually find out where to look for what in XenForo if I can't find it via the obvious methods.