When multiple menu items point to the same page, the active trail is selected from the higher-preference menu, even if the item in that menu is disabled.
Consider two menus:
- Nav Page One (node/1)
-- Nav Page Two (node/2) [disabled]
- My Page One (node/1)
-- My Page Two (node/2)
The active trail will show the Navigation menu item (Nav Page One) even though the menu item for node/2 is disabled.