Index: src/wp-includes/default-filters.php
===================================================================
--- src/wp-includes/default-filters.php	(revision 35378)
+++ src/wp-includes/default-filters.php	(working copy)
@@ -429,6 +429,7 @@
 // Don't remove. Wrong way to disable.
 add_action( 'template_redirect', '_wp_admin_bar_init', 0 );
 add_action( 'admin_init', '_wp_admin_bar_init' );
+add_action( 'signup_header', '_wp_admin_bar_init' );
 add_action( 'wp_footer', 'wp_admin_bar_render', 1000 );
 add_action( 'in_admin_header', 'wp_admin_bar_render', 0 );