Unable to nest categories in menu

Related Posts:

1. Display a portion/ branch of the menu tree using wp_nav_menu()
2. Programmatically add a Navigation menu and menu items
3. Any docs for wp_nav_menu’s “items_wrap” argument?
4. Customizing Only a Specific Menu using the “wp_nav_menu_items” Hook?
5. Changing the Order of Admin Menu Sections?
6. How make top level menu item not have link, but have sub-menus that are linked?
7. Add ‘has_children’ class to parent li when modifying Walker_Nav_Menu
8. Get WP Navigation Menu from REST API V2
9. How to Hard Code Custom menu items
10. How to add a Custom Link to a Menu with a URL that is relative to the blog URL
11. How do I remove UL on wp_nav_menu?
12. Retrieving a list of menu items in an array
13. WordPress default menu in database
14. Adding an Arbitrary Link to the Admin Menu?
15. Dynamically exclude menu items from wp_nav_menu
16. Add “Logout” link to navigation menu
17. Error: Declaration of MyClass::start_lvl() should be compatible with that of Walker_Nav_Menu::start_lvl()
18. Split up wp_nav_menu with custom walker
19. Removing container from wp_nav_menu not working
20. Custom Nav walker display current menu item children, or siblings on no children
21. wp_nav_menu: show menu only if one exists, otherwise show nothing
22. Is there an easy way to replace a custom menu link with a page or post?
23. Convert output of nav_menu items into a tree-like multidimensional array
24. Get page IDs from nav items
25. Add a custom walker to a menu created in a widget
26. Using a menu walker add a custom item at the end of the menu’s items
27. Add settings to menu items in the Customizer
28. wp_get_nav_menu_items() not working with slug
29. How to get current-menu-item title as variable?
30. Error “Trying to get property of non-object” with Custom Walker for wp_nav_menu
31. Add Class to Specific Link in Custom Menu
32. Remove a menu item in menu
33. Generate a Menu that Displays Child Pages using wp_list_pages() with the New Menu Functionality in WordPress 3.0?
34. How do I get the name of a menu in WordPress?
35. How to Add to Each Menu Link with link text to data-attr?
36. How to manually specify the current active page with wp_nav_menu()
37. How to count nav menu items?
38. How Does The Walker Class Work?
39. Add Javascript to WordPress Menu
40. Add custom menu item using wp_nav_menu_items filter
41. Filter wp_nav_menu()
42. How to modify navigation menu of the “My Account” page in WooCommerce
43. remove “edit your profile” from admin menu bar
44. WordPress Settings API, Implementing Tabs On Custom Menu Page
45. Adding line breaks to nav menu items
46. Adding category ID or slug to WP Nav Menu
47. add custom class to wp_nav_menu using filter hook nav_menu_css_class
48. Custom ID for certain menu item?
49. Does Extending Multiple Nav_Menu_Walkers Allow Nested Menus?
50. Check if page is in a certain menu
51. how to create a menu with all sub categories?
52. Making breadcrumb with wp_nav_menu
53. Does WP REST API have a built in route for calling menu?
54. How to avoid wp_nav_menu() ID conflict?
55. Add data-icon input to WordPress custom menu links
56. Registering menu with ‘Automatically add new top-level pages to this menu’ selected
57. Why do Custom Nav Menus generate so many classes on list items? Can I manage this somehow?
58. wp_nav_menu remove class and id from li
59. Custom search filter causes menu and query_posts problems
60. Unregister Nav Menu from Child-Theme
61. How does a minimal menu walker look like?
62. Add separator to admin submenu
63. fall back for main menu?
64. On which hook should I be calling register_nav_menu(s)?
65. WordPress Shortcode in Menu Item Title
66. register_nav_menus() won’t register menus
67. Calling the Menu Title within wp_nav_menu array function
68. How can I create an auto-populated menu that is automatically assigned to a location?
69. Display only page specific sub menu items using Custom Walker
70. How do I add a search box to the nav menu?
71. How to get IDs for objects in menu branch?
72. New post notification in wp_nav_menu
73. Custom Post Types posts as submenus in Nav Menu
74. Link to Author archive from Navigation Menus in dashboard?
75. How to stop mobile theme inheriting desktop navigation menu?
76. Add child pages automatically to nav menu
77. adding some custom html code to the wp_nav_menu function
78. WordPress Menu Custom Walker Class
79. Show just one level of child pages, wp_list_pages woe
80. Increase search results for Admin -> Appearance -> Menus -> Search (default is 10)
81. How to create this custom menu walker?
82. Removing link ” from ” menu for some “links” without JS
83. How to change order of menu items
84. Renaming a WordPress Admin Menu
85. Whats the difference between current_page_item and current-menu-item
86. Using nonce in menu item
87. Remove unusable metaboxes in nav menu management screen
88. Menu limit, cannot add new menu items
89. Highlight parent menu item when child is not in menu
90. Show current navigation path from menu
91. Deleted pages are NOT removed from custom menus?
92. How can I add (custom) modules to Appearance -> Menus?
93. Custom settings disappear during database migration?
94. Call custom field into menu item
95. How do I add nested categories to drop-down menu in twenty-eleven?
96. Use navigation path from menu for permalink
97. Add custom page link with anchor
98. Exclude Private, Draft pages from Primary Nav when using custom menu
99. Automatically remove trashed pages from nav menu
100. How to hide an item from a menu to logged out users (without a plugin)