Replaceing _custom_background_cb

You have 

wp_head_callback

as parameter at your arguments array, which is wrong.

It should be

wp-head-callback

which is the correct spelling.

Because of the wrong spelling the default value for wp-head-callback which is _custom_background_cb has been used, as the wrong spelling is unknown to WordPress – of course.

Related Posts:

  1. How to add CSS class to custom logo?
  2. How do I add settings to the Background Options Page?
  3. Editing the custom background CSS
  4. How to add default images for custom backgrounds?
  5. Add colors to existing color palette without replacing it
  6. Multiple Custom_Background, is it possible?
  7. What flex-width/height does?
  8. add_theme_support(‘my-custom-feature’)
  9. add_theme_support( ‘custom-header’ ) does not add option menu in dashboard
  10. Get background color for Live Preview with Theme Customization API?
  11. Weekly background code not working
  12. “add_theme_support” for custom footer color?
  13. Show video as part of the post?
  14. How to add theme support?
  15. Edit footer via customizer
  16. Theme Development: Starter Content after hook
  17. Can I add multiple arrays within add_theme_support( ‘colors’ )?
  18. How to use add_theme_support(‘html5’)?
  19. Theme support title tag – how to replace the default WP separator (with a filter)?
  20. Is there any way to register custom background images like header images?
  21. WordPress HTML5 Gallery Support – Convert HTML4 -> HTML5
  22. add_theme_support( ‘admin-bar’ ) causes fatal error
  23. What is difference between add_theme_support and Theme Customization API?
  24. background_image support multiple image size?
  25. How to Disable Color Options?
  26. Custom background not showing
  27. Theme’s featured image option is not showing up
  28. Adding a div to wrap widget content after the widget title
  29. CSS classes for theme
  30. How to edit bbPress template files – WordPress + BuddyPress + bbPress? [closed]
  31. Adding Content Areas to Custom Page Template
  32. Add class to before_widget for all widgets with a dropdown and a counter
  33. What is the best practice for customizing a plugin’s JavaScript/jQuery?
  34. Override default cropping in WordPress [duplicate]
  35. Trouble with conditional tags
  36. How to use Iris color picker on front-end?
  37. First post of each category
  38. create blocks programmtically on theme activation
  39. Possible to add “Template” selector to posts?
  40. Set front page as static page [closed]
  41. Adding LazyLoad and InfiniteScroll to WordPress Theme
  42. How Can I Create a List of Values to Be Iterated Through via WordPress Customization API?
  43. Adding default pagination to wordpress loop
  44. If I build a custom theme, will it update?
  45. Recommended tools for Theme Development with SASS [closed]
  46. Implement content-nosidebar.php / content-leftsidebar.php
  47. How to change i18n/l10n of #reply-title? (Old title: Comment reply link not working)
  48. What are the Entry classes for?
  49. Using an if statement in the theme customizer page
  50. Installing WordPress locally
  51. Custom markup with wp_nav_menu based on pages
  52. How to edit my theme for full width?
  53. What VSCode extensions are there for working with block themes? [closed]
  54. What is the “correct” way to add hooks or similar PHP behavior to a blocktheme?
  55. Fetch wordpress video attachment with post ID
  56. Echo all category names, apart from one
  57. Updating a live theme safely?
  58. How do I remove inline style in featured image markup?
  59. different way to achive stylesheet_url
  60. Why is my CSS not loading?
  61. How to find default functions of wordpress
  62. How to remove ver from stylesheet URL? [duplicate]
  63. wp_nav_menu with default pages menu
  64. How To Detect Posted Comment in Theme Development?
  65. using Options Framework – can “theme-textdomain” domain be changed?
  66. How to add sidebar to Isola theme? [closed]
  67. Change the sidebar from left to right twentyfourteen theme
  68. Custom theme won’t use search.php
  69. Get attachment meta (I need attachment ID, unsure how to find it)
  70. How to add testimonials with an image?
  71. How to setup sidebar modules to use jQuery Accordian
  72. Add class every 4 post like , class_1, class_2, class_3, class_4 and class_1, class_2, class_3, class_4
  73. Theme functions don’t work as expected in partial included via get_template_part() after custom query using Ajax [duplicate]
  74. How can I not disable my theme when I want to upload a new version of it?
  75. Avoiding do_shortcode() loops
  76. WordPress Post Order
  77. Why content is not adding for each blog post
  78. Correct was to customise theme using get_theme_mod in scripts
  79. Create image with imagepng() (fails at header)
  80. Dynamic meta description
  81. How to Remove Sidebar when get_sidebar() is not get called in page?
  82. RSS feed url showing page not found. How to solve it?
  83. Plugin or script to apply updated media settings to all featured images
  84. Header links also appearing in the footer
  85. Extending arrays in parent theme without completely overriding the files
  86. Retina ready for uploaded images which are cropped
  87. WordPress Subpages Fancybox Trouble
  88. Toolbox theme using printif statement – help needed understanding code block
  89. Search Results not displaying for multiple word search
  90. Allow users to edit home page from WordPress (home.php problems)
  91. WordPress does not know the parametrs i sent to admin post
  92. Display Page featured Image as well as Posts featured Image
  93. Custom Single Page Portfolio Theme [closed]
  94. Add wrapper for a specific sub-menu
  95. Meaning of “if ( is_home() && ! is_front_page() )” snippet?
  96. Not Able to Access Terms Under Custom Taxonomy Archive
  97. WordPress search field won’t get wider
  98. Custom add to cart does not work well only on the first time
  99. Trying to create a cutom query with pagination and page 2 breaking. Any help?
  100. Full Site Editing, Block Theme, Gutenberg, Site Editor