Twenty Twenty-One: Skip the untitled title filter in the admin

[itzmekhokan]

Twenty Twenty-One filters the_title to display "Untitled" for posts and pages that are missing a title. This is a front-end presentation concern, but the filter also runs in the admin.

What the problem was:

• Since #65022, the post list table shows a trimmed excerpt in place of a missing title, gated on '' === get_the_title( $post ).
• Twenty Twenty-One's filter fills empty titles with "Untitled", so that condition is never met in the admin. The excerpt fallback is suppressed and untitled posts display "Untitled" in the list table instead.

What the fix does:

• Adds an is_admin() guard to twenty_twenty_one_post_title() so the "Untitled" replacement only applies on the front end. Admin titles are returned unchanged, restoring the excerpt fallback introduced in #65022.

Approach and why:

• This matches the theme's existing idiom: the sibling callbacks twenty_twenty_one_continue_reading_link_excerpt() and twenty_twenty_one_continue_reading_link() already use the same in-function is_admin() check. It is the smallest change that resolves the ticket and does not alter front-end behaviour.

Trac ticket: https://core.trac.wordpress.org/ticket/65710

Use of AI Tools

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[Copilot]

Pull request overview

This PR adjusts Twenty Twenty-One’s the_title filter so that the theme’s “Untitled” replacement only applies on the front end, avoiding unintended admin UI changes (notably the post list table’s empty-title excerpt fallback introduced in core).

Changes:

• Add an is_admin() guard to twenty_twenty_one_post_title() to return the original title in wp-admin.
• Update the function docblock to note the front-end-only behavior.

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