There's no longer a reason to re-render the header on Design updates

app/views/profiles/update.js.erb

 // Remove body class for any previous theme, re-add current one
 $('body').removeClass('<%= Gitlab::Theme.body_classes %>')
 $('body').addClass('<%= app_theme %> <%= theme_type %>')
-
-// Re-render the header to reflect the new theme
-$('header').html('<%= escape_javascript(render("layouts/head_panel", title: "Profile")) %>')