Controller or its method is not found: \\App\\Controllers\\Home::index

When you enable csrf filter, you get 303 if you don't send correct token with the POST request.
>> But that equals a redirect?

If CSRF token is not sent or correct, CI4 redirects by default if not Ajax request.
See https://codeigniter4.github.io/CodeIgnit...on-failure

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$routes->get('/Testing', '\AppXXX\Controllers\Testing::testmethod');
With $routes->setAutoRoute(false); the route doesnt work but with it set to true, it works.  Sorry, how is that possible?

> With $routes->setAutoRoute(false); the route doesnt work.
It means the route definition is something wrong.

> $routes->get('/Testing', '\AppXXX\Controllers\Testing::testmethod');
It means
When you navigate to https://your.site.example.com/Testing, \AppXXX\Controllers\Testing controller's
testmethod() is executed.

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> but with it set to true, it works.

It means you have \App\Controllers\Testing controller, because
auto routing can only execute controllers in app/Controllers/ directory.

Anyway, you can check all routes by spark routes command.

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