Adding a 'Drop-down Menu' is a good way to group menu items. For example, a “Genre” collection. A 'Submenu' is a good way to group different collections. For example, adding an “Action” or “Comedy” collection in the “Genre” menu item.

Step 1:

Go to the ‘Content’ tab then select ‘Navigation’.

Step 2:

Select ‘Add a Menu’ and add the name of the menu item, e.g. "Genres", and click ‘Add’. You can also do this to add the 'Submenu' items.

Step 3:

Add the 'Submenu' items you have created by dragging and dropping them under the menu item you added above.

Step 4:

Once done, select ‘Save'.
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