Admin: Avoid using HTTP_HOST to build admin URLs.

[himanshupathak95]

Trac ticket: https://core.trac.wordpress.org/ticket/16858

WordPress admin constructz the "current URL" by manually concatenating $_SERVER['HTTP_HOST'] with $_SERVER['REQUEST_URI'] these places:

• WP_List_Table::pagination() — pagination navigation links
• WP_List_Table::print_column_headers() — column sort links
• wp_admin_canonical_url() — the admin canonical <link> tag

When WordPress runs behind a reverse proxy, HTTP_HOST reflects the internal backend hostname, not
the public-facing WordPress URL, causing these links to point to the wrong host.

Testing

Run tests by -

npm run test:php -- --filter=Tests_Admin_WpListTable

Use of AI Tools

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Props dd32

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