I think a better way is to implement #[\AllowDynamicProperties]
Shorter and easier.
I give you my changes.

/system/core/URI.php

#[\AllowDynamicProperties]

class CI_URI {

/system/core/Router.php

#[\AllowDynamicProperties]

class CI_Router {

/system/core/Loader.php

#[\AllowDynamicProperties]

class CI_Loader {

/system/core/Controller.php

#[\AllowDynamicProperties]

class CI_Controller {     

/system/core/DB_driver.php

#[\AllowDynamicProperties]

abstract class CI_DB_driver {

I think a better way is to implement #[\AllowDynamicProperties] Shorter and easier. I give you my changes.

/system/core/URI.php

#[\AllowDynamicProperties]

class CI_URI {

/system/core/Router.php

#[\AllowDynamicProperties]

class CI_Router {

/system/core/Loader.php

#[\AllowDynamicProperties]

class CI_Loader {

/system/core/Controller.php

#[\AllowDynamicProperties]

class CI_Controller {     

/system/core/DB_driver.php

#[\AllowDynamicProperties]

abstract class CI_DB_driver {

Thanks, but thats a bit of a hack for lazy people. IDE auto-completion would be more grateful for the explicit declaration of the properties on the class; so will developers...

If that's the route the maintainers want to take then thats up to their discretion, personally never used codeigniter 👍

#6173

I think a better way is to implement #[\AllowDynamicProperties] Shorter and easier. I give you my changes.

/system/core/URI.php

#[\AllowDynamicProperties]

class CI_URI {

/system/core/Router.php

#[\AllowDynamicProperties]

class CI_Router {

/system/core/Loader.php

#[\AllowDynamicProperties]

class CI_Loader {

/system/core/Controller.php

#[\AllowDynamicProperties]

class CI_Controller {     

/system/core/DB_driver.php

#[\AllowDynamicProperties]

abstract class CI_DB_driver {

Thanks a lot.
It's really working.
I needed to use Codeigniter v3.0.6, but the Codeigniter source normally made some errors, until I found this troubleshoot.
Thanks a lot again.

right.so you can use Trait without change core like this
we need autoloads like application/core/MY_URI.php

#[\AllowDynamicProperties]
class MY_URI extends CI_URI {}

and application/core/MY_Router.php:

#[\AllowDynamicProperties]
class MY_Router extends CI_Router {}

and another classes
now codeigniter load perfix MY_ in owner class list
check perfix in your config.php file

$config['subclass_prefix'] = 'MY_';