Implode error after upgrade cake 3.5 to 3.6

[ Deprecated (8192)](javascript:void(0);): implode(): Passing glue string after array is deprecated. Swap the parameters [ CORE\src\View\Helper\SecureFieldTokenTrait.php , line 53 ]

This was fixed in CakePHP 3.8.3 so just continue to upgrade your app and fix YOUR deprecation erros on the way.

The Core deprecation errors will disapper as you get to higher versions.

Thank you after upgrading to 3.8 indeed above error disappear but now i have this one [ Deprecated (16384)](javascript:void(0);): RoutingMiddleware should be passed an application instance. Failing to do so can cause plugin routes to not behave correctly. - C:\wampphp7.4\www\upgrade\vendor\cakephp\cakephp\src\Http\MiddlewareQueue.php, line: 90 You can disable deprecation warnings by setting Error.errorLevel to E_ALL & ~E_USER_DEPRECATED in your config/app.php. [ CORE\src\Core\functions.php , line 311 ]

should i upgrade to more latest version. Thank you very much.

Did you adjust your src/Application.php like it is currently present in the cakephp/app 3.x branch?

Thanks for your response. Indeed as per your suggestion I upgraded to 3.8 then most of the errors disappeared but regarding this error what i did is that
I actually made a fresh installation of the 3.8 version and then I transferred the changes so that i don’t miss anything in skeleton so far it is working now. Thanks for your help.

if your app is so “small” that you can easily create a new app and transfer your logic then I highly recommend you to use the current CakePHP 4 version.

Can i migrate to 4.x automatically as i have removed the deprecation warnings from 3.10. Thanks