When the environment variable APP_DEBUG is set to 0, Zikula will catch and render all exceptions as an error page. Very much like Symfony, the developer can override the templates to customize the user experience.

The original template is @ZikulaThemeModule/Exception/error.html.twig

This template can be overridden in the usual manner - both in the theme and in the /templates directories.

In addition, the renderer will attempt to locate an error-specific template according to this pattern:

`sprintf('@ZikulaThemeModule/Exception/error%s.html.twig', $statusCode)`

e.g. `@ZikulaThemeModule/Exception/error404.html.twig`

This should also be located in the theme or /templates directories as desired.

note: When APP_DEBUG=1, Symfony's own error handler will display the full trace on the error instead.