Many PHP warnings in Apache error log when opening any page or post for edition in wp-admin

[dailymatrix]

After upgrading to 6.5, and still on 6.5.2, when opening any page or post for edition in wp-admin, I'm getting many PHP warnings in the Apache error log referring to wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php.

However, it does not seem, so far, to have any noticeable effect in the normal edition workflow.

Specifications:
Ubuntu 22.04.4 LTS
Apache/2.4.58
PHP 8.2.17

Here, an excerpt from the log:

[Wed Apr 10 20:03:15.663768 2024] [proxy_fcgi:error] [pid XXXXX:tid XXXXXXXXXXXXXXXXX] [remote XXXXXXXXXXXXXXXXXX] AH01071: Got error 'PHP message: PHP Warning:  Attempt to read property "id" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 647;
PHP message: PHP Warning:  Attempt to read property "theme" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 651;
PHP message:PHP Warning:  Attempt to read property "content" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 658;
PHP message: PHP Warning:  Attempt to read property "content" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 662;
PHP message: PHP Warning:  Attempt to read property "slug" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 666;
PHP message: PHP Warning:  Attempt to read property "source" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 670;
PHP message: PHP Warning:  Attempt to read property "origin" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 674;
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 678;
PHP message: PHP Warning:  Attempt to read property "description" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 682;
PHP message: PHP Warning:  Attempt to read property "title" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 690;
PHP message: PHP Warning:  Attempt to read property "wp_id" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 694;
PHP message: PHP Warning:  Attempt to read property "title" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 698;
PHP message: PHP Warning:  Attempt to read property "status" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 703;
PHP message: PHP Warning:  Attempt to read property "wp_id" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 707;
PHP message: PHP Warning:  Attempt to read property "has_theme_file" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 711;
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 714;
PHP message: PHP Warning:  Attempt to read property "author" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 719;
PHP message: PHP Warning:  Attempt to read property "modified" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 727;
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 769;
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 769;
PHP message: PHP Warning:  Attempt to read property "author" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 829; 
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php on line 769;
PHP message: PHP Warning:  Attempt to read property "type" on null in /var/www/mysite/wp-includes/rest-api/endpoints/ .......(many more)', referer: https://mysite.com/wp-admin/post.php?post=11209&action=edit&lang=es

[jorbin]

Hi @dailymatrix, welcome to WordPress Trac. Thanks for the ticket, this has been reported in #60909