Various errors detected since WP 6.3

Hi,
I just upgraded to WordPress 6.3 and some errors are thrown by XML Sitemap when visiting sitemap-author.xml. A blank page is displayed an Apache log reports :

PHP message: PHP Fatal error: Uncaught Error: Call to undefined function switch_to_blog() in /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/class-wp-user-query.php:1077, referer sitemap.xml

stderr: #0 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/class-wp-user-query.php(829): WP_User_Query->generate_cache_key(Array, '\\n\\t\\t\\t\\tSELECT wp_...'), referer sitemap.xml
stderr: #1 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/class-wp-user-query.php(80): WP_User_Query->query(), referer sitemap.xml
stderr: #2 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/user.php(775): WP_User_Query->__construct(Array), referer sitemap.xml
stderr: #3 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-content/plugins/xml-sitemap-feed/models/functions.public-sitemap.php(71): get_users(Array), referer sitemap.xml
stderr: #4 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-content/plugins/xml-sitemap-feed/views/feed-sitemap-author.php(21): xmlsf_get_author_data(), referer sitemap.xml
stderr: #5 /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/template.php(785):...n /home/clients/56e2f1092650a93981e5ea2ac69b6745/web/blog/wp-includes/class-wp-user-query.php:1077, referer sitemap.xml

There is only one author on my blog, so I deactivated the option. But it may be useful for other users.

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