Description

Removing theme support for block templates on a site that has a pre-existing template added by a user results in a white screen error on the front end.

Step-by-step reproduction instructions

1. Add a new template (either from "Create new template" command in the Page Editor or in the Site Editor > Templates > "Add New Template")

2. In twentytwentyfour/functions.php add the following lines from curating the editor experience documentation:

function example_theme_support() {
    remove_theme_support( 'block-templates' );
}
add_action( 'after_setup_theme', 'example_theme_support' );

3. Reload the website home page and see a white screen.

Screenshots, screen recording, code snippet

No response

Environment info

WP 6.6
no Gutenberg plugin
Twenty Twentyfour theme
Chrome
Mac

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

• Yes