Ever been annoyed at why those helicopter control rate sliders sometimes seem to move unexpectedly? I've figured it out..

The sliders can be dragged with right-click (and surprisingly middle-click) as well as left-click. You don't normally see it because right-click closes the menu.

Try this: open the menu, place the mouse over one of the slider handles (ready to drag), then right click to close the menu. Now move the mouse around. Only the cursor is disabled and doesn't move on the menu. Now right-click but hold the button: the menu appears and moving the mouse moves the slider handle with it.

Recommendation: only left-click (and mouse wheel) should interact with the UI.