Categories do no show on main page when the setting in Layout Settings > Categories - Always Show on Main Page is set to "1". This worked in Zen Cart 1.5.7. I have tried with my custom template and the base Zen Cart template and neither one shows the categories on the main page.

I am no PHP coder but it appears to be an issue with includes > modules > pages > index > header_php.php. When I replaced the 1.5.7b version of this file with the one from 1.5.7 (just to see what would happen), the categories do show on the main page (though the dots separating the rows and columns don't appear).

Not sure if this is a bug or I am being dumb about how to make this work.

Test Site:
https://www.moonrivercardstore.com/test_OPCO/

Zen Cart 1.5.7b
PHP 7.4