When I add bookmarks to the bookmarks toolbar, they don't appear on the bookmarks toolbar (duh...) but appear instead in the Bookmarks Toolbar submenu inside of the Bookmarks menu.
How do I get them to appear on the bookmarks toolbar itself?
You can check that the "Bookmarks Toolbar items" is still on the Bookmarks Toolbar.
If the menu bar is hidden then press the F10 key or hold down the Alt key to make the menu bar appear.
Make sure that toolbars like the "Navigation Toolbar" and the "Bookmarks Toolbar" are visible:
Open the Customize window to set which toolbar items to display: